#help-19
1 messages · Page 122 of 1
$(n-1)\sum_{i=0}^{k-1}n^i$
Pop
$\frac{n^k}{\sum_{i=0}^{k-1}n^i}$
Pop
Yes
its the same
I'm satisfied with this being called simplified
Yea but u just used sigma
Lol
im closing the section
Mhm
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.reopen
how do i do this, im not sure how to start
@cedar geyser Has your question been resolved?
<@&286206848099549185>
@cedar geyser Has your question been resolved?
hey wsp!
note that the hydrostatic pressure is P=dgh where P is the pressure, d is the density of the fluid, g is the acceleration, and h is the depth
how can you use this to find the answer?
(apologies if this is incorrect)
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Can somebody explain why this is wrong?
I used the normal approximation and used 3.5, 6.5 to account for continuity correction
BTW n = 14
p(4<= x<= 6) = p(-0.84 <= Z<= 0.84) = p(z<= 0.84) - p(z<= -0.84). Is this correct?
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Because these related points can not be expressed in integers
It fked me up
Let me know how would you guys solve it
Could you please post a picture of the original question instead? Kind of hard to read it when it is as a video.
I cannot
I already skip this one in the web
I think you can press the stop button
Then it would looks like a picture of certain frame
I feel like some information is missing.
Look not looks*
thank you
that is illusive
I don't follow.
You're wondering about the website's solution?
@elder vault Has your question been resolved?
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I am confused in how this works anyone pls
Easiest way to do this
is to determine which letter is on the opposite side of A
The question gives u three options
for letters
A,E,E,E,M
so try to see if you can eliminate any of these
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hi imma need some help to get through the steps
what have you understood till now?
Tbh not sure what to do after I figured out part a. Idk how to approach part b
I tried out factoring and foiling out the polynomial and got 4x(x-8)(x-4) idk if thats right tho
find the derivative and make it =0
,w expand x(16-2x)(8-2x)
yes
that is correct
f' is what you wrote
now find the value of x that gives the max volume
@stone swift Has your question been resolved?
Yep thx
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How do you divide polynomials
ex 3x²+3x+1/x-1
I dont get it
u know long division for 3505/5
ig you should watch a tutorial for that
here in chat it is difficult to explain and you'll most probably don't even get what we try to explain
find it on yt
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I was curious why this direct substitution for a, b, and c is possible
like what path to go to if it were to prove that this are the only combination that is right
that positive integers made only one combination of a, b and c possible
for example if they just gave integers, there could be a possibility of negative integers, so there could be another combination
but here it is not that case
Lambert proved that pi is irrationnal with thoses
how come however I wont be able to use this reasoning for other equations? like per se
a+b = 6
a+b = 5+1
therefore a=5 and b=1.. but it could also be a=4 b=2
given that a and b are positive integers in here
here the fraction and their numerators being 1 played a huge role
due to them possibility of other combinations could be rejected
If multiple answers were possible, they wont ask for the sum and further more they arent multiples, cuz the only way to write 50/7 like b+1/c its 7+1/7, with others numbers theyre wouldnt be a 1 on top.
Its just to precise where does they takes values
So its from $\bN^3$
YakuBros
make sense, I guess I was coming from where its a problem I've encountered myself and not given by a sample paper
so I sort of disregarded the reason 'they wont ask for the sum if there arent precise values'
But if it wasnt given, your process is really good
b >= 1 and 1/c > 0 so b+1/c > 1 so 0< 1/(b + 1/c) < 1 so a < 3.14 < a+1 but a is a positive integer so a = 3.
Then (1/b + c) = 50/7 and you proceed similarly
even if there's a case where they want you to get just one combination but you get any other combinations, the question setters will give some other condition that may help to reject the other ones and to consider only one of them correct
$3.14 = \frac{314}{100}$
Newt
easy a = 3
kinda got lost with 0<1/(1/b+c)<1 implying a<3.14<a+1
and where 1/(1/b+c) came from
add a to all sides
just to clarify, its 1/b+c not 1/[b+(1/c)]?
oh yeah
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Pre-calc Conic Sections : Circles

Read on it
Or watch a YouTube video
How does the $r^2$ work here?
Beersathought
I mean, I know that in a circle all points are equidistant to the center, but like what is the r^2 here exactly?
r is the radius, since the radius is 4, itll be 4^2=16
for the $(x-h)^2 + (y-k)^2 = r^2$
Beersathought
yeah
Is it because adding them all up = 16 or whatever?
Isn't r^2 = 4 here?
wouldnt that mean the radius is 2 then?
um im not sure
yeah
in the diagram it has a radius of 4, not 2
but counting the radius its 4
when you're writing the equation of a circle with centre (a, b), the equation will be like (x-a)^2 + (y-b)^2 = r^2 where r is the radius of the circle
using this formula, you have found your points and found out the radius is 4 by counting the length, thus your answer is (x-3)^2 + (y+5)^2 =4^2, since you know r=4, thus giving (x-3)^2 + (y+5)^2 =16
yuh and the questions tells us r=4, so after subbing in r=4 into r^2, it gives 4^2 = 16
yeah, but in this case, I'm wondering how the (x-h)^2 + (y-k)^2 = r^2 works, like the equation in general
Cause I don't really know where r^2 comes from if that makes sense
(x-3)^2 + (y+5)^2 = 4
(x-a)^2 + (y-b)^2 = r^2
4 is in place of r^2 here though?
ahhh um sorry i cant help with that as im not too sure myself, i was learnt on how to use that equation but ig this equation tells us the centre point of the circle and the length of its radius
the reason for that is because a circle is basically all the points that are a certain distance from a specific point (the centre), we calculate the distance of 2 points with a formula
I see
4 isnt in the place of r^2
if you look beersathought got did 4 = r^2 and got marked wrong
What's the reason for them being squared?
yeah
oh mb didn't see that it's marked wrong
let's use your question as an example
we already know where the centre is (3, -5)
yea
so we want to find the equation for all the points that are 4 units apart from (3, -5)
In this video we look at the proof of the equation of a circle by considering Pythagoras’ theorem and how we can form a general equation of any centre and radius.
oh
Alrighty, I'll check this out afterwards
if we represent those points with (x, y), when using the distance formula we'll get to sqrt((x-3)^2 + (y+5)^2) = 4
i believe this is the formal proof, and explains where your squares and radius comes from, if it doesnt help you could try googling proof for the equation of a circle
all we're doing is raising both sides to power 2, I'm assuming just to make it easier to write
Alright, thanks a lot
if thats the case then it will be
$\sqrt{(x^2 - 6x + 9) + (y^2 + 10x + 25)}$
Beersathought
that's what happens lol
so in the end we'll have $(x-3)^2 + (y+5)^2 = 16$
nima
I see
notice how the radius also gets squared in the process of removing the square root, that's why it's r^2
cheers!
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Bob?
do you have an actual question?
@junior mango Has your question been resolved?
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
!da2a
No need to ask “Can I ask…?” or “Does anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/
Bro tried to use root privileges 💀
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Ohhh sorry
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Is the question wrong here? I think it should be (x+y+z)³ = 3(x³+y³+z³) in the second part.
Question 15.
When I solved the question provided here the answer appears to be (x+y+z)³ = 27xyz. Is it correct?
Is a³ + b³ + c³ = 3abc?
For this one? Wait let me attach my answer.
yup that would be better (abt attaching ur ans)
Here.
how have you taken this?
I don't exactly remember. But I think I took this from some other equation's answer.
uhm
Well, something clicked in my brain and now I solved it. Thank your for your help though.
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ive tried using the factorizations of 2554 and doesnt seem to get me anywhere
i translated the question so it looks kinda weird
is that supposed to be the floor function
yes
its alright
,w arccos x = 2pi
...?
i'm starting to think maybe its just the difference of squares of 2555 and 2554
<@&286206848099549185>
is this the question copter ?
yes
can you explain how you thought that
well i realised that if you let n be 2554, after the 1227th term its all just the first term since it has the floor function
maybe im just overcomplicating it
its the floor function
oh ohk
i dont really know where to start though
sorry am pretty busy now i think it might took some time
i am getting deja vu feeling rn
maybe later
this is an old question from an 8th grade competition im going to so im just kinda confused on where to even begin
for example
i thought of that too
alright thanks
2555/2 = 1277.5 = 1277
its floor function
and
2444/2 = 1277
and i think it will repeat
no worries copter
yea it repeats
im gonna put other questions from the test here later
it would be this
oh okay so its just a difference of squares then?
yea
np
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,w 2555^2 - 2554^2
wait can you reopen?
.reopen
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?
yeah but wouldnt there be two a1 terms on both?
ohh
2554 will have 1 term less
so its 5110 then?
the questions didnt say
just keep n=0
A1 = 1 though
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I don’t understand this
what’s on the RHS
coz basically
as cos gets smaller, why does the length increase?
so you have a doubt in the concept?
I just want to understand it
cos is base/hypotenuse in triangle
cos is directly proportional base length (and hence inversely to length)
from the pythagoreom theorum, a^2 + b^2 = 1, so if a decreases b increases
okay thanks guys
analyse it on some basis and you can get it on your own too
geometry helps a lot in the analysis
Focus on the ratios not the length
yup
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Can anyone help me please #help-21|아리스킨충1
Please don't occupy multiple help channels.
I just see people who are just opening tickets getting help for for mine its been over an hour
I wont do it in the future though mb
@wary helm Has your question been resolved?
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Is this correct?
Yesh
Oh wait nvm I didn't read the left picture
Nah this is totally wrong
They're asking you to write an expression
☠️ why this is giving me GPT vibes?☠️
Not solve for anything
my friend give me this he say its correct 😭
So uh the two cars head in directions perpendicular to each other correct
So that's your pythagorean theorum
it is the most stupidest thing to trust on it in terms of maths
sqrt(9850)*t would be the expression
yea i got Distance = 10 x sqrt(98.5) x t
would it be better to just put what u got
Idk do you need as simplified as possible
ima just put yours seems more logical
or idk
thanks
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Translationm: Find the lowest point of:
i got 16sqrt(11) but idk if its right or not
at x = sqrt 11
not correct unfortunately
why? could you help?
first i simplified x - a/x into (x^2 - a)/x
this is probably where im wrong
i factored |(x^2 -a)/x| into |x^2 - a| 1/|x|
no that's not wrong
,w minimum value of (sum from r=1 to 20 of |x - r/x |)
what is wolfram on
what did you do after this
first does it make sense that the minimum occurs at some sqrt(n) where n is an integer
you can assume x is positive without loss of generality
nope because equality doesn't hold for each term at the same point
and that
yes realised lately
well it simplifies to (x^2 - a)/x so i assumed so
turned it into [|x^2 - 1| + | x^2 -2| + ... |x^2 - 20|] 1/|x|
then using the formula to find the median of the roots you get 10 <= x^2 <= 11
what formula?
that works for |x+/-a| things only
ohh
thought it worked for x^2 too
then what do i do then?
from here you can get away with doing this problem just by plugging in values of sqrt(n) and finding the smallest
though there may be a better solution
"if f(x) = |x - a1| + |x - a2| +... |x - an| and n is even the lowest point of f(x) is in the range median <= x <= next value" here i assumed f(x^2) worked
oh okay
(btw you evaluated the expression at sqrt(11) incorrectly)
it might work but a 1/|x| is also in multiplication with it
well this would have worked if there wasn't that |x| factor in the denominator
ohh😭
first, can you justify why the minima/maxima MUST be at one of the values sqrt(n)?
hmm yeah this doesn't look too easy unfortunately
maybe try using the triangle inequality
desmos says 29.399
by the time you find a solution to algebraically "prove" the minimum this approach would already give you the answer
i think if you use the triangle inequality on the first and last terms and going in from there you'll get a factor of 19
why do you think the minimum will be necessarily at a sqrt(n)?
i don't really see why this is so obvious
summation of cusped functions typically have a minimum at one of the cusps
and also time consuming
if this appeared on a test that's exactly what i would do
ngl same but id get lazy after 4 tries
by checking on geogebra it seems to be that the minimum is at x=sqrt13
You only need 4 or 5 tries, you can binary search it
indeed
binary search?
this isn't even necessary
intuitively, the minimum should be close to n = 11
Well sure
desmos says the same
i really do not like this logic though
every step is riddled with non-motivated assumptions
if it works for you i guess it works
I mean there is a final step you should do, but I don't see a faster way
ive put like 4 of the questions from this test on here and all of them everyone brute forced or guessed😭
welcome to computational-style competition level math
though yes i agree this problem is not really that good
there must be a more elementary way to solve this
if you check the sequence of minimas
it does seem to follow kind of a random pattern
since this test is for 7th - 9th graders
no fucking way what
the solution probably involves finding a general form for f(n)
bro's a Thai genius
but even this takes longer than just plugging in values
i highly doubt there is one
oh there definitely isn't
judging from the other questions they all have reasonable ways to the solution
but once you correctly evaluate f at any value of sqrt(n) then doing more will be easy
you can probs justify this with concavity/convexity
its from like 12 years ago though
i mean, did you try the triangle inequality at all?
im sure that has atleast some use here
yeah that makes sense now that I think about it
sqrt(n) are the only critical points of the graph and the graph is also continuous except at x=0
you could try differentiating that ungodly mess
It's not guaranteed, which is why I said there is a final step
Look at the same sum but with 10 as upper bound
This could be how a solver/CAS does it, apart from just graphing it somehow and searching minima from there
It would likely be a waste of computational power since you can't do (d/dx)=0, you need subgradients and check for wherever it goes from negative to positive
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what is LHD and RHD coming here
for x=2
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I need help what steps do I take in order to find the value of a baseball card
Please @ me when you see this I may be off discord
what was your process in getting these inputs you have
4K I divided 493/363=e13k 13 representing the years between 1977 1990
Then I inputed the answer and got 263e^0.048t
263 but yeah that checks out, what are you struggling with then?
And then I subtract 2015 and 1977 and got 38 and then put it for the equation
Part D what is doubling time for the value of the baseball cards the nearest tenth of a year
you seem to have a good grasp
ah
it means how long does it take the value of the card to double
solving 2(263)=263e^(0.048t) would be enough
Okay I will try that
See I got confused on which values to input
14.44056626?)
And just rounded up right
I think I tried 14.44 and it said it was the wrong answer
,w ln(2)/0.048
14.4?
si
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Wait one more question how do I do the last part section e
I need help with the last part section e
throw an idea at me
not quite
remember what the equation you found actually means
A=263e^(0.048t)
t is the years after 1977
A is the value at time t
Si
so A=2260
then we find t to know when that value is achieved
@tiny sigil Has your question been resolved?
@cold sage
This is alright, but you need to solve for t
Like how we found the doubling time
So solve the equation to find t or substitute t with a value
@cold sage sorry I know you're probably busy ^^'
Its alright, yeah you need to solve for t, very similar to the way you solved for d
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I dont get how they get a^22 as the derivative. Why is it not product rule of a^22 and x so 22a^21(x) - a^22 ?
What is the derivative of f(x) = ax where 'a' is a constant?
a?
Why would they not say that lol
Becuz it's already given
gotcha, thanks!
Haha, never mention brudder
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clikz
looks well done
Btw you couldve found a function of the side bisector of those 2 points then just plug x = 0
clikz
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@void spire like this?
Yes
oh ok I understand
Idk if its easier. But i think it could be
I mean geting the slope and midpoint is easy. Then basically just plug it in y = ax + b to get b and that is your answer
yea I think that way is better
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Why did we put n * s instead of n * p? doesnt the full p (everything that is in the second screenshot) represent the vector of the line?
looks like pi is a plane, not a vector
you can tell by this that if r and n are orthogonal that the plane pi and line p are parallel
yes but n is the normal vector of pi
yea
so we put the vector of n * the vector of the line p
if you were to move the vector r onto the plane pi
wouldnt they be parallel to p?
thats the equivalent to seeing if n and r are orthogonal
and I dont understand why we dont use this form of the vector and only use the direction vector s of it
you can take in fact any vector that points in the same direction as p
the direction vector is just the most convenient one
you can also take this one
as long as it's in p or at least parallel to p
what about the size of n and r, dont they have to be the same size to be = 0 aka on a 90 degree angle?
no
the angle doesnt change
just because you change size
take triangles for example
I dont get it
no matter how much you scale the vector
the angle remains
because the direction doesnt change
oh ok true
and i took triangle as an example
cause you scale its lengths (but proportionally cause it's closed) the angles still remain
so because s and n are on a 90 degree angle then no matter what they should be = 0
yea
could we take anything other to figure out that n * that something else = 0 when a normal vector and a line in this form is given?
I'm guessing not, right?
any multiple of the direction vector can be taken
multiple as in s * a scalar?
yea exactly
wait so K here is a scalar or a point on the line?
oh yea true
wait so with this we actually get the point vector of r no?
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I dont understand this
with this function we are calculating the point vector of r right (what is inside the red box of the second screenshot)?,
the point of vector?
why is r twice appearing?
,,\vec{r} = \vec{r}_r + k \cdot \vec{s}
𝔸dωn𝓲²s
You are basically at r_r and from there you are going into the direction of the vector s
point vector, as in a point in space that has a vector from 0 to it
oh sorry it may be some other name in English
our teacher usually uses r to annotate that we are we can insert a point at r to get the point vector
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I’m pretty confused on this topic in general but to be more specific I’m confused how to find the vertical and horizontal displacement. Im
Not sure how to decide which coordinates to subtract from the other
do you know how to calculate the hypotenuse of a right triangle?
Yea, a^2+b^2=c^2
I’m sure I can just find the lengths of the base and height and find the 2/5 of each but that’s not the way khan academy wants me to solve it
now, find a hypotenuse of the line such that it has the value $\frac{2}{5}\cdot AC$
boss
then obtain the needed value for y
Alright hold on
$\frac{2}{5}\cdot AC = \frac{2}{5} \cdot \sqrt{101}$ if i read everything correctly
boss
Then what?
This is getting more confusing if anything since all the answer choices are whole/mixed numbers coordinates
then you know how much you need to go right from point B such that $AB = \frac{2}{5}\cdot AC$
boss
from this you can calculate the y value using the linear function that goes thru A and C
$f(-8+dx) = y_B$
boss
where $dx = |-8-x_B|$
boss
What does the d stand for?
"how much do i need to go right from point A to reach B on the linear function AC"
thats the meaning behind dx
interesting notation
idk better xD
I really appreciate the help but this made it more confusing+i didn’t get my question answered on how to find the vertical/horizontal displacement of 2 coordinates😭
relax
well do i
can you please be more precise on what you do not understand?
Alright hold up let me try to comprehend it step by step
take your time
If we know the coordinates of A
and AB is just 2/5 of AC
wouldn't that be applicable on the coordinates as well?
some boss shit
hihi
But in order to do that, you need to find the vertical/horizontal distance, where from you add to to the coordinates of A since it is asking for the line of AB
what you need to find is:
A step dx such that the red line has the lenght of $\frac{2}{5}\cdot AC$ from A
boss
maybe start by defining the linear function that goes thru A and C
do you know how to do this?
linear functions are fully defined by 2 points, so there exists a concrete formula to calculate the needed coefficients
$f_{AC}(x) = m\cdot x + b$ you need to find m and b
boss
This is how I understand it and that’s the answer, and i got the vertical/horizontal displacements by looking at the graph, but I’m confused on how to find it when I’m just given coordinates and i can’t see a graph
but there is clearly a graph thru A and C, its blue. maybe i dont understand
thats a similar question
Sorry i should’ve showed that type of question first lol
What does the X stand for?
I’m trying to use your method for this problem
the $x_B$?
boss
Nah the x in the dx
you mean the $dx$?
Yes
boss
try to see it from the perspective of being at point A:
"how much do i need to go right from point A to reach B on the linear function AC" = dx
Yea but how would I get a coordinate from that
$x_B = -8 + dx$
boss
and you know that $2/5 \cdot \sqrt{101} = \sqrt{(dx)^2 + (f(dx))^2}$
now solve for dx
boss
as i already mentioned you first need to calculate $f(x)$ but this is trivial since you have the coordinates of 2 points lying on $f(x)$
boss
I tried using your method for the most recent problem i showed you
Did I miss out on anything?
Cuz the answer is crazy😭
boss
because that means that you have moved more than you want since: $10.7703 < \sqrt{10.7703^2 + 10.7703^2} = \sqrt{2} \cdot 10.7703$
boss
What is the point in finding the amount of space that is 2/3 of line AC?
well you want to solve the problem dont you?
what do you mean by "space" ? and "2/3 of line AC" ?
have you solved this?
maybe you are better in explaining?
From my perspective, 10.7703 is the distance from A to B(the space) which is 2/3’s of A to C
idk if it's right
Sorry if I’m being difficult😭
I just noticed both triangles are similar
Since we know the green
if we get the angle at C for example
and we know the hypotenuse (length of AB) then we can get the other red sides
and thus the coordinate change from A to B
very intelligent aswell!
a more geometric approach
like it.
my approach is maybe too deep into analysis..
Isn’t that like trigonometry since we have to find the angle?
yea
i hate trigonemtry but in this case
turns out it's easy if you use it
haha
what is the question?
well done guys
yea true (wtf is SAT)
wtf is a kilometer?
Well using my method/khan academy’s, I was confused on how to find the vertical and horizontal displacement of 2 coordinates
Which i know is x2-x1, and y2-y1
dont you use the formula (nx1 + mx2)/m + n?
But I’m confused if it matters which coordinate we use for x1,y1, and x2,y2
where the line is split into m:n
Hold up doing it rn
you get B(5.6, ) and smth else
I’m doing it for this problem
Like this?
@tacit haven
W equation if it works for problem like these
you need to understand the formula
not just use something
that wont carry you thru university
It didn’t give me the right answer so it isn’t right but i might be doing it wrong, but if it gave me the right answer i think I would understand it
I realized I learn best when I learn in reverse and analyze why that got that
i would show him the proof but i forgot how to do it
How come M is the numerator and N is the denominator?
the formula is used for when line A is split into m:n
Do you mean N=all the pieces and M=the amount of piecies its asking
since AC is split into 2:3, you can substitute
I’m thinking visually btw
m + n is the whole line
Where did the 2:3 come from, in the equation it says 2:1
mbmb
yeah m = 2, n = 1 if you are referencing it from point A
so for this question if you let point A be (x1,y1) you get the x coordinate to be (2 - 8)/3
which is -2
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yo for this do i convert the amounts into decimals
so instead of 4 ft 2 inches i should make it as the proper decimal which is 4.167
?
better to work with improper fractions
hmm
so in this case i got my answer thru decimal and fraction form as 25 feet
would that be correct or incorrect
i get a bit shaky with fractions sometimes
but then iagain i js use a calculator
yes, 25 is correct
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yo i also forgot
?
its a proof i have to fill out
and i have to use those things wiht dropdowns as reasons
but im so lost
because its saying XY but thats not shown in the model
please
im desperate!!!
i know which are true, but i dunno the names of why they're true
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What am I supposed to do ?
What do you already know from the equation?
is this a test by any chance
That it is in a slope intercept form
no
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
^^
i studied this chapter 2 months back but now i dont remember a thing
y = mx + b
the slope should be negative ?
good
What do the parts of this equation represent?
so which options does that eliminate
c and d
no...
try again
you said that the line formed by the equation has negative slope
so, which options would that eliminate?
😭 no
im cooked
Negative slope means that starting from the left moving to the right it is going downwards
a and d ?
oh
do you understand slope now?
you sure?
yeah.. but i still dont know how to identify a graph just from the given slope
but you understand why b and c have been eliminated right
correct
how'd you get there?
wait what
no not c
slope can also be explained as rise over run
did you mistype
$\frac{rise}{run}$ or $\frac{how_far_up}{how_far_over}$
yeah ik this
$\frac{\text{rise}}{\text{run}}$ or $\frac{\text{how far up}}{\text{how far over}}$
with the same logic applied
ren
thank you
are you just guessing
np
yeah
okay listen to me
we are trying to help you learn
and are also giving you clues
but if you disregard all of that
and just guess
y = mx + b
m = slope
b = y-intercept (where the line crosses the up and down axis)
there's no point to all of this
im sorry
alright
how do i apply this to my equation
Well, what is the b in the equation you have?
Choose two points on the line and find the difference in height and length
3
but i am i supposed to know which lines to choose
Which of the graphs that you have left, show to intersect at the 3 on the y axis
a has -3 and d +3
The perfectly up and down line that is thick is the y-axis
The perfectly left and right line that is thick is the x-axis
The third thick line is the line of the equation
So, is your b positive or negative?
there are so many points intersecting which ones should i use to identify the slope
See how those two lines cross at "perfect spots" they cross at intersections of the y and x axes
Well I would choose points you can perfectly describe
ohh
see how the graph passes directly over a whole number on the x axis?
yeah
I would use that as one of your points as you can perfectly describe it
Where else does it perfectly cross at a point like that (Doesn't have to be across the x-axis)
im getting 1/4
i choose (2,0) and (6,1) as my points
i think they perfectly intersect
Yep!
not (-1, -2), you seem to have (y, x) it's typically written as (x, y)
oh my bad
yeah, you will get an equivalent answer that when simplified will give you 1/4, as you solved for here
No problem
just look at where the graph passes over the y-axis