#Needing help on similar triangles for geometry pls and thanks

548 messages · Page 1 of 1 (latest)

terse treeBOT
soft thunder
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are you familiar with tangent?

worthy summit
soft thunder
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have you heard of sine and cosine before?

worthy summit
soft thunder
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okay so basically there are three functions which can be applied to right triangles

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sine, cosine and tangent

worthy summit
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Okay and what does that mean?

soft thunder
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each one of them describe a ratio between certain sides of the triangle in regards to an angle

worthy summit
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oh okay i understand now, the part i get confused with it when to add and subtract the congruent sides of the two triangles that overlap

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and how to set the equation up properly

soft thunder
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these are the side of a right triangle when viewed from any angle

worthy summit
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Okay got it

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this is the problem right now, and i don’t know where to add or where to subtract to start the equation

soft thunder
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that's why you should let me finish

worthy summit
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sorry

soft thunder
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here, this is what the ratios look like for each function

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now when we apply this to your problem can you name which sides we have currently measured?

worthy summit
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hypotenuse?

soft thunder
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the hypotenuse is the longest side, opposite of the right angle in the triangle

worthy summit
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ohhh, so would it be the adjacent side that is already measured?

soft thunder
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not only that

worthy summit
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opposite as well?

soft thunder
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now give me the measures for both sides

worthy summit
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opposite= 120.24m adjacent=130m

soft thunder
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.25 but yes

worthy summit
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yes sorry i just recognized my error

soft thunder
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any ratio we could use?

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or function, rather

worthy summit
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120.25
————
130

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?

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sorry i tried my best to make a fraction

soft thunder
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not a problem

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don't forget the units

worthy summit
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okay sorry

soft thunder
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so it would be 120.25m/130m

worthy summit
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okay got it

soft thunder
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now if you punch that into your calculator and hit the tangent function, what do you get?

worthy summit
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is there a fraction button on an iphone calculator?

soft thunder
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uhm

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just type 120.25 divided by 130

worthy summit
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okk

soft thunder
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a fraction is just a division in the end

worthy summit
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0.925

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is what i got

soft thunder
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yep

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now we actually don't use tangent but cotangent

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which is the inverse

worthy summit
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Okayy

soft thunder
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right now we have 0.925 which is the ratio which we can convert back to an angle

worthy summit
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how do we do that?

soft thunder
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by using the cotangent function

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do you have that on your calculator?

worthy summit
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i think there’s a button that says “tan”

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is that it?

soft thunder
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yes

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but that is tangent

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you will need the inverse

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so cot

worthy summit
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i may not have that i have cos and tanh

soft thunder
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do you have a secondary function on your calculator?

worthy summit
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yes

soft thunder
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try to press that

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maybe it gives you cot

worthy summit
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it doesnt show it says same things with like a -1 at the top of each function

soft thunder
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yes

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that is the inverse

worthy summit
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oooh ok ok, so which would i press? cos-1?

soft thunder
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tan^-1

worthy summit
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okay so what numbers do i put into it same ones?

soft thunder
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remember, we were using the tangent function since we had a ratio of opposite to adjacent

worthy summit
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0.925?

soft thunder
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yes, 0.925

worthy summit
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42.76

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is what i got

soft thunder
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that doesn't sound right

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are you sure you had 0.925 and hit the secondary function before pressing tan?

worthy summit
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ill try again

red prairie
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I need some help too

soft thunder
worthy summit
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yes i got 42.76882539 and so on

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but i have to round the nearest hundredth of a meter

soft thunder
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well it gives me 61.936 approximately

worthy summit
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tan^-1 right?

soft thunder
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yes

worthy summit
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yeah i got the same number again

soft thunder
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hm, try resetting your calculator

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type in 0.925 and then try again

worthy summit
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yeah i got the same thing

soft thunder
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can you show me a screenshot if that's possible?

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or are you using an analog device

worthy summit
soft thunder
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what happens when you hit tan?

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with the 0.925

worthy summit
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0.016

soft thunder
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now hit the 1/x

worthy summit
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0.016 converts to 62.5

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but with 0.925

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goes to the 42 number and then to 61.93

soft thunder
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aha

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well I think your calculator is a bit faulty

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you should maybe get an analog one

worthy summit
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yes i agree

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so i have to go to tan the 1/x

soft thunder
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yes for now that will suffice

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I recommend using an online calculator tho

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anyways

red prairie
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Helpppppp

soft thunder
red prairie
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I am new

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How to open?

soft thunder
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#❓how-to-get-help

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or #1021175428326633542

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so now that we have the 61.936

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can you tell me what that number means?

worthy summit
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opposite?

soft thunder
worthy summit
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hypotenuse / adjeent?

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adjacent*

soft thunder
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repeat to me what we just did please

worthy summit
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we divided 120.25m by 130m

soft thunder
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because of what?

worthy summit
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which was opposite over hypotenuse

soft thunder
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that is incorrect

worthy summit
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oh

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we used the tan function so opposite over adjacent

soft thunder
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exactly

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now what are we aiming for with that?

worthy summit
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x

soft thunder
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if you remember I mentioned that it's a ratio regarding an angle

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do you see the θ?

worthy summit
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no i dont

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oh wait yes sorry

soft thunder
worthy summit
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i thought u meant the problem

soft thunder
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ah no

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for now I want to clarify why we did this

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you can see it says tan θ

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correct would be tan (θ) btw because it is the tangent of theta

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can you tell me what θ is?

worthy summit
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61.93

soft thunder
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yes

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but also what is θ

worthy summit
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the answer coming out of dividing opposite and ajdacent

soft thunder
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look at the picture again

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look to the right

worthy summit
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the right angle

soft thunder
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where is the symbol

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θ

worthy summit
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inside the triangle to show the angle

soft thunder
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exactly

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it represents an angle

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this is very important

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so the tangent of theta (written as tan (θ)) is equal to the ratio of opposite to adjacent

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which is why we inversed the ratio with the cotangent to "restore" the angle we are searching for

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do you understand this?

worthy summit
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yes i do

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so the answer would be 61/93

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61.93*

soft thunder
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well if we were searching for the angle then yes

worthy summit
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Okay let me try putting it in

soft thunder
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but we will have to do one more step

worthy summit
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Oh okay

soft thunder
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we are not searching for the angle in your problem

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we are searching for the length of VW

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but what can we do now that we know the angle at point U?

worthy summit
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add that with 70m?

soft thunder
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think in mathematical terms

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what are we searching for?

ancient panther
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You don't need to use tangent to solve this problem. This is a question abt similarities and ratios

worthy summit
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the missing variable? or the length of VW

soft thunder
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...

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we are onto something here I don't understand why you would have the urge to barge in

ancient panther
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Because obviously he hasn't learned trignometry yet

soft thunder
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so what

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you take away his freedom by deciding for him whether or not he should be learning this stuff now

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I think oz7 would've let me known if he was against the way I am trying to get this through

worthy summit
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yeah i dont mind

soft thunder
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precisely my point

ancient panther
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So triangle VWU and triangle XYU are similar triangles,
VW:XY=VU:XU

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I'm just trying to say there's a simpler solution

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Sorry to interrupt, I'll leave now

soft thunder
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you should've said it at the end

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so now that you know there's an easier method, which one do you prefer

worthy summit
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continue with yours

soft thunder
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alright

worthy summit
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id rather learn this early so i understand it next year

soft thunder
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love it

worthy summit
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yes

soft thunder
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okay let's refresh

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we have established an angle of 61.936 at point U

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by using the cotangent

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we also know that we are searching for the length of VW

worthy summit
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indeed

soft thunder
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using this picture once again

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can you tell me what VW could also be viewed as?

worthy summit
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opposite

soft thunder
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you're getting the hang of this

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so what can we use to calculate it?

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look closely at your problem and at the picture I provided and you should be able to figure it out

worthy summit
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opposite and hypotenuse

soft thunder
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remember, hypotenuse is opposite of the right angle and the longest side

worthy summit
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ohh oky so opposite and adjacent again?

soft thunder
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you can't use the opposite to calculate the opposite

worthy summit
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good point

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so then adjacent and hypotenuse?

soft thunder
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look at the left side

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remember what we calculated

worthy summit
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im not sure

soft thunder
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what function did we use?

worthy summit
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opposite and adjacent

soft thunder
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these are just names, not a function

worthy summit
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ohhhh

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tan and 1/x

soft thunder
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yes

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let's just say cotangent

worthy summit
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thats the one we use for VW?

soft thunder
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no that's what we used to reverse the ratio into an angle

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remember?

worthy summit
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yes i remember

soft thunder
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okay good

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so spin up these brain cells of yours

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what measures do we have at hand which could be useful to calculate the opposite?

worthy summit
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XY

soft thunder
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you can do one better

worthy summit
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XU?

soft thunder
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close

worthy summit
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YU?

soft thunder
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precisely

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what is YU?

worthy summit
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61.93

soft thunder
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no that was the angle

worthy summit
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its the hypotenuse?

soft thunder
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is it opposite of the right angle?

worthy summit
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yes? i think

soft thunder
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if you look at the picture the square indicating the right triangle is right next to point Y

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so it's adjacent, not opposite of the right angle

worthy summit
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ohhhhhhh

soft thunder
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what is YU then?

worthy summit
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adjacent

soft thunder
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only one option left

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you got it

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and what is its measure?

worthy summit
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120.25m

soft thunder
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careful

worthy summit
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im not sure of the measure

soft thunder
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nvm I fucked up

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I didn't see the points

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I meant VU the whole time

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YU was the hypotenuse

worthy summit
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ohhhhhhhh

soft thunder
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LMAO

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excuse me

worthy summit
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all together VU woulld be 200m?

soft thunder
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yesyes

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omg that must have caused a lot of confusion

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I'm a terrible teacher

worthy summit
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lol its okay dw

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no ur not ive learned a lot so far

soft thunder
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thanks but that's really shouldn't have happened

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panik

worthy summit
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haha its ok

soft thunder
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yeah let's continue

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let's use my trusty picture again

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can you tell me what to do?

worthy summit
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we have to do adjacent over hypotenuse

soft thunder
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remind yourself of what measures we calculated so far

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write them down

worthy summit
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VU

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and point U

soft thunder
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not point U

worthy summit
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Yu?

soft thunder
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no we calculated the angle at point U

worthy summit
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ohh ur right sorry

soft thunder
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and what was VU again?

worthy summit
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200m

soft thunder
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and furthermore?

worthy summit
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Vw is 200m

soft thunder
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what

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no

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I was asking for what VU is else

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apart from 200m

worthy summit
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hypotenuse?

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cause yu was adjacent

soft thunder
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no I mixed it up

worthy summit
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so VU is adjacent?

soft thunder
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yes

worthy summit
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ok got it

soft thunder
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since it is adjacent to the angle, but not opposite of the right angle

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the hypotenuse is also always the longest side on top of being opposite of the right triangle

worthy summit
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so it will always be thee longest side?

soft thunder
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the hypotenuse will always be the longest side, yes

worthy summit
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okayy

soft thunder
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so now we have the adjacent VU with a measure of 200m and the angle at point U with a measure of 61.936°

worthy summit
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correct

soft thunder
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and we are searching for the opposite

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what is our only option to solve this problem then?

worthy summit
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function sin

soft thunder
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how

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you would need the hypotenuse

worthy summit
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so cos?

soft thunder
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I just said we have an angle, the adjacent and we are looking for the opposite

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no hypotenuse

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whatsoever

worthy summit
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so the only option left is tan

soft thunder
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yes

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the tan function seems to be working on your calculator

worthy summit
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yes it is

soft thunder
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so you can put the measure of the angle in there and tell me what the result is

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but

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if you are really smart you already know the result

worthy summit
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0.925?

soft thunder
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and why would that be

worthy summit
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because 61.93 came from 0.925 and therfor just reverted back

soft thunder
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because we used the inverse of the tangent on 0.925 to restore the angle it follows that if we use the tangent on the angle we get back our ratio of opposite to adjacent, in this example 0.925

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but yes, you got it

worthy summit
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woo okay okay

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what we do from here

soft thunder
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well now we have a fairly simple equation

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0.925 = opposite/adjacent

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you should be able to figure this out, if not let me know

worthy summit
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so would the equation be 0.925/200?

soft thunder
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careful

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you want the opposite to stand alone on one side of the equation

worthy summit
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0.925/x = 200/61.93?

soft thunder
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0.925 = opposite / 200m

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how do you get rid of the 200m on the right side?

worthy summit
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im confused

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subtracting

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200

soft thunder
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it's a fraction

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you can't just subtract

worthy summit
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dividing 200?

soft thunder
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the opposite is being divided by 200m already

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why would you want to divide it by a further 200

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that would split it into even more parts

worthy summit
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but whats the opposite im confused on that

soft thunder
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the opposite is VW

worthy summit
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so if VW is the opposite

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and VU is adjacent

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which is 200

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than the adjacent is YX?

soft thunder
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no the adjacent is VU

worthy summit
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hypotenuse?

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sorry i typed without thinking properly

soft thunder
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look

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0.925 = VW / 200m

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I can't make it easier without solving it

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let's take a little detour

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to explain what you are meant to do

worthy summit
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okay ya cause i still dont know how to solve

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it

soft thunder
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if I give you the number 1

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and then tell you to split it into 2 parts, how would you write that?

worthy summit
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1/2

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so 0.5

soft thunder
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was about to say

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so how do you get back your 1 now?

worthy summit
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0.5x2

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equals 1

soft thunder
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keep the fraction

worthy summit
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1/2

soft thunder
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now do the same thing

worthy summit
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200 would be 100 in two parts

soft thunder
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please stay here

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don't wander off

worthy summit
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okay i wont

soft thunder
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1/2, how do you get back your 1?

worthy summit
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by adding another half

soft thunder
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no

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that's not what this is about

soft thunder
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you did it before

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I just wanted you to write it as a fraction

worthy summit
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0.5/2?

soft thunder
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what did you write

worthy summit
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0.5x2/1

soft thunder
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you wrote 0.5 x 2

worthy summit
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yes

soft thunder
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all I want is for you to use fractions

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don't use 0.5

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that's literally all I wanted

worthy summit
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erm

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so

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would it be

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5/2

soft thunder
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what happened to your 1/2

worthy summit
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idk how to make it to afraction

soft thunder
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you made 1/2 into 0.5

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that was you

worthy summit
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yes

soft thunder
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but anyways

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so you have your number 1, I told you to split it into 2 parts

worthy summit
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yes

soft thunder
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what was that again?

worthy summit
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0.5

soft thunder
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no

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fractions

worthy summit
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1/2

soft thunder
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yes

worthy summit
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IT WAS THAT ALL ALONG??

soft thunder
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yes..

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xD

worthy summit
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omg im dumb

soft thunder
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no this is a crucial step

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please split the 1 into 519 parts now

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write it as a fraction

worthy summit
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1/519

soft thunder
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now into a million parts

worthy summit
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1/1000000

soft thunder
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how would you go about restoring your shattered 1 now?

worthy summit
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by reverting it back to the fraction

soft thunder
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what mathematical operation would you need to do

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on 1/1000000

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to restore the 1

worthy summit
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divide by 1 million

soft thunder
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real quick

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what is the opposite of -

worthy summit
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posotive

soft thunder
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I want to see a sign

worthy summit
soft thunder
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what is the opposite of /

worthy summit
#

.

soft thunder
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meaning?

worthy summit
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decimal

soft thunder
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have you not had multiplication and division yet?

worthy summit
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i have

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OHHHH

soft thunder
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why is the opposite of dividing not multiplying then

worthy summit
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my bad i didnt relize u meant division

soft thunder
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how else would you visualize division

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whatever

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now that we established that

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what do you need to get back your 1 that has been shattered into 1 million pieces?

worthy summit
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multiply

soft thunder
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by?

worthy summit
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1000000

soft thunder
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and what about the 1/519?

worthy summit
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multiply by 519

soft thunder
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what about the 1/2?

worthy summit
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by 2

soft thunder
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now

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prize question

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opposite/200m

worthy summit
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multiply by 200

soft thunder
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200m

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but yes

worthy summit
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yes

soft thunder
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and since it is an equation

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0.925 = opposite / 200m

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you need to do it on both sides

worthy summit
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so multiply by 2oom on both sides

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200m*

soft thunder
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you got it

worthy summit
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0.925=185

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and 200= 400

soft thunder
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hey now

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1 = 1

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how can 200 = 400

worthy summit
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oh so its still 200

soft thunder
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look

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let's take another little detour

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1 = 1 right?

worthy summit
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yes

soft thunder
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if I tell you to multiply by 2, what does it have to look like?

worthy summit
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2x1

soft thunder
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you need to keep the equation

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the = sign

worthy summit
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wdym

soft thunder
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well 1 = 1

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now multiply by 2

worthy summit
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2=2

soft thunder
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yes

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but in essence it would be 1x2 = 1x2

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got it?

worthy summit
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got it

soft thunder
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now

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0.925 = opposite / 200m

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multiply by 200m

worthy summit
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0.925x200=200x200?

soft thunder
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where did the opposite go

worthy summit
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0.925x200=Opposite x 200

soft thunder
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let's go back to the 1/519

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how do we reverse it?

worthy summit
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multiply by 519

soft thunder
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but we wouldn't have 1 x 519

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we would just have 1

worthy summit
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yes

soft thunder
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how did we go from opposite / 200m to opposite x 200m then

worthy summit
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cause id have to multiply by 200 both sides right

soft thunder
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but only once on each side

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of the = sign

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you did it twice on the right side

worthy summit
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so how do i do that with the division sign still there

soft thunder
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remember 1/519?

worthy summit
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yes

soft thunder
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it's the same sign

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you multiply by 519

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to get rid of it

worthy summit
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yes

soft thunder
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same with the opposite / 200m

worthy summit
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so i have to multiply 200 to get rid of it

soft thunder
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you multiply by 200m to get rid of it

worthy summit
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so would it be 185=opposite?

soft thunder
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don't forget the units

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but you got it

worthy summit
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185m= opposite

soft thunder
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yes

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congrats you solved it

worthy summit
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so thats the answer?

soft thunder
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yep

worthy summit
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wow, thank you so much

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u really taught me a lot

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thank you

soft thunder
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I'm kinda suprised you pulled through this well

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well done

worthy summit
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lol i felt like i did bad

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i got confused a lot

soft thunder
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I think with a bit more practice you will get this in no time

worthy summit
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i agree

soft thunder
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we spent a few hours on this

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and look where we are

worthy summit
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i know haha

soft thunder
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I would call this good progress

worthy summit
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it really helped

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me too

soft thunder
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keep it up!

worthy summit
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thank you!

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thanks for being so patient

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and thanks for your time as well

soft thunder
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always a pleasure

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if you are done you can close the ticket with .close I believe

worthy summit
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okay thanks

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you have a good rest of ur night or day

soft thunder
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you too

worthy summit
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.close