#help-23
1 messages · Page 421 of 1
so the vertical slices arent even disks, you cant use the disk method like you did originally
you could use shell method though, if you know it
You mean washer or the cylindrical?
cylindrical shells
Yess
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Chat what topics do u think will be on gcse's im going to priortise revising them
(I do foundation)
Maybe look at tests from a year or two ago
Maybe but its not always accurate
Plus
Its less likely they'll ask more of repeated topics
ask in #study-discussion or #math-discussion rather than opening a help channel, this is more for specific math problems
Oh. Thanks
.close
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I’m really confused on how to get exponential function equations from graphs that have HA
<@&286206848099549185>
!15m
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Oop
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Oop
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Omg
once is okay😭
got sniped again 🥀
Ah yes !15m dogpiling
I’m scared
In any case, what are you confused about?
what do you mean by HA?
sorry i didnt see it was already done; as a result @burnt oyster let this be a lesson to not repeat it again
Horizontal atmosphere
u summoned the helpers
<@&268886789983436800> troll
dont troll in help channels, especially an occupied one
what's confusing you exactly?
So basically when there’s a horizontal atmosphere that means there’s a transition and im confused on finding b
I think you mean asymptote btw
My teacher said you can use any point but when I do that and look at the answers it doesn’t work
Yea
Ok so for example the asymtope is 1 is I add one to the y values of the current values to to get the new value of the transformation right?
Then with those I get the difference for and that will be the value or b in y=ab^x
Answwrddd
Is anyone able to do 6 with me so I can understand better?
I’m not sure how to get b
how did you get 2 = a^4 + 1
oh wait you have it here
how did you find out its 2^x

My teacher was helping me and she said the difference of 2 and -2 is 4
So the x value doubles each time?
uh i dont quite understand your work, but its not correct
y = ab^x + 1
until here, it is correct
at this point, I'd focus on finding a
try to look at the point where x = 0
I see 0,5 and 1,3
okay and what happens when you plug in 0,5?
Add 1 to the y value
. in this
you dont need to add 1 to the y value
just plug it in as x = 0 and y = 5
Y = ab^0 0+1
MathIsAlwaysRight
No
okay so the curve was described by $y = a\cdot b^x + 1$
MathIsAlwaysRight
and you know that the point (0, 5) lies on it
Yea
when a point lies on a curve, it means that it satisfies the equation
so when we plug in x = 0 and y = 5, the equation will be true
i just replaced x with 0 and y with 5 (So i plugged in the point (0,5))
I see
now you can simplify this and solve it
as a hint, notice that b^0 = 1 (thats why we plugged in the point with x = 0 first - itll make b disappear)
ill gtg for a min, so you can solve it in the meantime
careful with pemdas
5 = a * 1 + 1
multiplication is done first
its not a * (1 + 1)
its (a * 1) + 1
Still a
so its 5 = a + 1
Isolate the a so subtract 1 on both sides 4=a
so a is 4
Yay
$y = 4 b^x + 1$
MathIsAlwaysRight
1,3?
plug it in and solve
which is 1/2
$y = 4\cdot \left(\frac{1}{2}\right)^x + 1$
MathIsAlwaysRight
So I ca use this formula
generally the procedure is to first find the horizontal asymptote
in this case it was 1, so thats why the +1
Can the point be interchangeable or for a should it always be 0 and another number
0 is definitely easiest
because it makes b^0 dissappear into 1
if we tried sth else, then b would still be there
and we would have a and b in one equation
which is quite difficult to solve
I see
- find HA
- find a, by plugging in the 0 point
- find b, by plugging in any other point
Thanks I’ll definitely use this for my practice
np
Wait what’s the normal equation without the numbers
@brave wolf sorryyy
@burnt oyster Has your question been resolved?
y = ab^x + c
sorry i was offline
c is the horizontal asymptote
@burnt oyster Has your question been resolved?
Nope
Now I’m confused with when drawing the inc and Dec graph because inc and Dec goes different ways I know I answered but it’s because I looked at the answer sheet
How can I know which way is it decreasing or increasing
I found this what do they mean by slope?
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✅ Original question: #help-23 message
I should know these stuff it in elementary school I didn’t put much attention to math until my grade matters like in highschool so I’m tryna be better
Basically, if the base that has the x on the exponent is smaller than 1 and bigger than 0, for example, (1/2)^x, the curve decreases. If it's bigger then 1, the curve increases
For example, 2^x will look like the first function, and (1/2)^x will look like the second one
The reason it's because raising a number between 0 and 1 to an exponent bigger then 1 will make the number smaller as in 0.5^2=0.25
So as x increases the value of f Will keep decreasing
Hope you understood
But like right to left and left to right how do we know
I kinda do thanks
Tbh I don’t lol
I’ll try and find a video I guess
If 0<the base<1, it will look like this:
It’s just like all 4 of those graphs increased and decreased in different ways how do I know which way to start left or right
Is the base is bigger than 1, it will look like this:
A and c decrease in different ways
In a), the base is 0.5, in b) the base is 4, however, its multiplied by a negative number (which flips it horizontally), in c) the base is 0.5, but it's also multiplied by a negative number, and in d) the base is 4
Because the base in a is 0.5 and in c is 4
Ohh
If you don't understand I request help from someone else lol
I get it now
Nice then
Thanks
No problem
What about the inc one
Same thing
Which one?
The graphs can inc in different ways because the base is neg or positive ?
D and b
I see
Can I also have a model for Dec.. hehe I’m sorry
The model is really helpful
Thankssss
You're welcome!
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Any ideas on how to calculate the area?
Cutting out parts like if it was cookie dough would work
by calculus or geometry?
😭
-# geometry is easier here tbh
Ngl I would make this a calc problem yeah
Yeah, I tried to divide it on 4 sections. Something like this. (sorry for the perfect drawings lol)
1 is nothing, so I assume is 0.
2 is a circle, so it's pi . r ^2, and I take 1/4 of it.
3 & 4 are kinda confusing for me idk why
"Use calculus to find the area)
What
There is a big triangle from 3 and 4
So, this is the right idea, wrong execution
-# bleh, thatd take too much time
Yeah im stupid
I think two sections is all you need
See how the right can be just a single triangle
?
Nah dw, stuff gets easier when u do it once
cookie cut out of the circle and the triangle
The entire thing yes. Fill that in mentally, and the circle. You can find those 2 areas you filled in right? So now you have
Mystery shape area - circle/4 - triangle = solution
Now just find the mystery shape by inverting what you just did, "building" it
The whole area is b.h = 4x8 = 32
(4x4)/2 = 8
(4x8)/2 = 16
black area = 32-24 = 8
ye? 😭
Hm, close
well, the whole area of the section 2
So if you wanna keep trying urself don't read this spoiler:
||after filling in the big triangle to the right and the quarter circle, you have a rectangle with a triangle on top. That is the mystery shape||
But feel free to cheat by reading it if you are not into learning more than this/are stuck
you only need the base and height of a triangle to find it's area right
but you actually can find the base
and the height is also labeled
Why is this wrong
oh wait I didn't even check yeah the calculation is right
I forgot to share my 3 possible answers, all of them include pi so that's why i tried using that way
i don't know where the hell i get 4 pi
Circle area?
may i suggest an alt method,
instead of dividing right side of the square as 3 and 4, why not treat it as the triangle in upper side of 4, with sides 4,4,4sqrt(2) and the other big triangle in 3 as a triangle with sides 8,4,4sqrt(5)
then its simple subtraction of areas?
so you found the area of the triangle region but now you can find the area of the circle part
Uhh I think its 4^2 * pi for that circle, then divide by 4 to get the quarter
||the simplest way is the triangle has base 4 (from the right) and height 4, so (1/2)(4)(4) = 8||
thats what i js said?
oh you were saying a subtraction of areas?
yeah
the area of the whole triangle is this
Yeah, step 2; #help-23 message
pi . r ^2, and I take 1/4 of it. =
pi . 4^2 = pi . 16
pi . 16 / 4 = 4 . pi
none of them has 16 pi

-# As in area of big square - quarter circle - quarter sqare - triangle(in part 4)- traingle (in part 3 and 4)
right I'm saying you don't need to do that
now 2 of them has 4pi
nw you good
-# its the fastest and most straightforward tho
-# anyways ill not spam js glad op got it resolved
my method is split the whole region down the middle: on the right side the triangle has area 8 because it has base 4, height 4 and the left side is the square - circle as op said. I'm pretty sure that's faster
but whatever works ig it doesn't matter
yes this is right
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I need help with sketching
Im genuinely terrible at graphing, do you mind drawing a rough sketch of it all for me?
ok wait 2 mins
Thank youu
try to study the variations of f at least
there you go
for the variations of f and its graph
dont mind me in the background 
basically it's a paranoïa pointing downwards because of the négative coefficient of x²
has 1 max at f(3)=4
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kinda weird terminology question. i know there are terms like "dodecahedral" and "tetrahedral" for things related to dodecahedra and tetrahedra. is there a similar term for things to hexagonal tilings?
dodecahedra and tetrahedra are polyhedra whereas hexagons are polygons. what are you looking for exactly
ur reflection im crine
i think having al at the end describes the shape of soemthing else in comparism to the polygon?
i'm not sure i understand ur question
just google it
i'm trying to describe something which kinda makes sense if you think of a tiling as a polyhedron with infinite faces, so just saying "hexagonal" wouldn't exactly be what i'm looking for
i tried googling it and didn't get anywhere
are u talking about inf repeating tiles?
yes
there is no regular polyhedral with hexagonal faces
ur talking about a 3d shape made up of regular hexagonal faces?
No hes talking about tiles and patterns
p sure the term hes looking for is honeycomb then?
If he doesnt want hexagonal
i'm talking about a theoretical infinite volume polyhedron whose faces are hexagonal
that doesnt exist dawg
yes i know
um hexagonal tiling or honeycomb? what it doesn't make sense
this is the name
yh he wants that but each tile is the face of an infinite polyhedron
all polyhedra have finite volume
“of inf volume”
Fr bro wants an infinitely large sphere atp
so um a ball
i know it doesn't actually exist
it was a generalization my classmates and i had talked about in my discrete math class years ago and i'm trying to talk to some people about it and saying "hexagonal tiling related" over and over is getting tiring so i was just curious if there was another term that could be used for it
ok
if you take out the silly "infinite volume" this could be one polyhedron
hmm cool
sphere 
basically ball
but um not quite yet

stop pinging me thx
fah
Yh cus esentially if u have n tiles and u approach infinity u get a sphere
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idk if im just dumb but how do I do 6.25 / 5 without a calculator
Plenty of ways
do you know what 625/5 is
25^2/5 so 5^4/5 so 5^3 which is 125
$\frac{6.25}{5} = \frac{625}{5} \cdot \frac{1}{100}$
multiply numerator and denominator by 2 
knief
you can always also do $\frac{6.25}{5} = \frac{6.25\times 2}{5\times 2} = \frac{12.5}{10}$
Annie Maqionde
are you asking?
oh i thought you were asking if we had another method lol
i mean this is both divisible by 4 and 3 so it's divisible by 12
i mean long division exists, and you can use it?
i only know how to do it for polynomials 😭
since 56 is divisible by 4 and 18 is divisible by 3 (3 + 4 + 5 + 6 = 18)
you can do 3600 - 3456 = 144
yea 12^2 but idk how you know 3456 is div by 3 and 4 tho
i just told you
^
where did the 56 come from?
you just need to look at the last two digits
if that number is divisible by 4 then the whole number is
really?
yes
because the rest of the digits can be split as a multiple of 100 which is divisible by 4
so any 3 digit plus number is just a multiple of 100 plus whatever number the last two digits make
so like 3040 is div by 4?
yes
if you understand this then it's trivial
you can make a similar statement for multiples of 8
i'm sure you know about multiples of 2
you just look at the ones digit
this is because we can just take the rest of the digits as a multiple of 10 which is a multiple of 2
do you understand what i mean
more or less yea
you don't sound convincing
no it makes sense
4
you mean the last 4
🤔
uh see if the last 2 numbers are div by 16 -> 4^2 or just some multiple of 4
oh nvm since we want to know whether or not 16 not a multiple of 16
not multiple but like words....
how to check if a number is divisible by 8?
if the last two digits is div by 8 then the whole number is
idk if that applies for 8 as it does 4 tho
Result:
39.5
so you lied...
not entirely, the div by 4 makes sense but everything else was just a bit to process
i.e. if you gave me a question i wouldn't really know how to begin
was divisibility by 2 too hard?
if you understood divisibility by 4 then it should make sense for 2, and then for 8, and so on...
for 4, if last two digits are div by 4 then the whole number is div by 4. So for 2, its just its some even number and 8 i dont really know
it's great that you can memorize the rule but you clearly didn't listen to my explanation of where the rule comes from and why it works
because if you did you'd be able to extend it to higher powers of 2
sorry
like it makes sense for 4 and 2. But understanding 8 and thus extending it to higher powers of 2 I am struggling with
like reading it over I assume by extend it we look at the next two numbers?
so for 316
31 isnt div by 8 therefore 316 isnt?
well for 2 i write the number as a multiple of 10 = 2^1 * 5 plus the ones digit
for 4 i write the number as a multiple of 100 = 4 * 25 plus the remaining tens plus ones digit
do you see where i'm going with this
so for 8,
we write it as 1000 = 8*(something [i assume 125?])? plus the remaining hundred, tens and ones digits?
yes
for simplicity we can start writing the other thing as 5^some power
it doesn't really matter
so with this information, im still confused with how to continue
with 3456?
no with like, showing it is or isnt div by 8
showing what is
316
well it's not divisible by 8
is that bc 316 is less than the thousand we need?
here there are only 3 digits so you'd just have to know or find a close enough multiple of 8 and see if the difference is a multiple of 8
yea it's useful for breaking down 4+ digit numbers
hmm ok, so something like 714 isnt div by 8
well yea it's not even divisible by 4
yea since 14 isnt div by 4
that's another easy thing to do
you're welcome
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What did i do wrong in 5?
what is the actual question?
<@&268886789983436800>
Mr beast scammer
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think he's done
Oh right
.close
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how do we determine the formula?
Well did your teacher teach you a step by step solution to solving these?
-# that or just R3= R3-4R1
Cuz technically there is no wrong answer, you can solve it any way you like
"the solver is never wrong, it's the question that is wrong"
I mean i assume it was still an augmented matrix
so how do I do this
augmented matrix is when the vector aka the constants after the = sign, integrated into the matrix
I mean typically you want to bring the matrix into row-echalon form
Ever heard of that?
Yeah so do that
See if it works
You want to create a sort of staircase
Start by eliminating the x1 term of R2
Ohh wait
I mean to get the answer in the question you just need to check which row operation was done between the first and second augmented matrix
wait lets restart
Yes
so what do I do again?
This
to get the answer in the question?
Check which row was changed between the first and second matrix. Then the row operation will be
(that row) = (that row) + (some constant) * (another row)
is the first augmented matrix converted to the second? and we're trying to tell what the transformation was?
Yes
Yes, so the row operation should look like R3 = R3 + cR?
I just meant c * (some other row)
There are two ways you can get rid of the first entry in R3. Either remove 4R1 or remove 2R2 (from R3)
So just check which of those two gives the row you get in the second matrix.
do u mind if i step back a bit an just get my head around the basics of matrices?
as x− 2y = 1 has infinitely many solutions, since once
y is specified, then x is determined and conversely.
how?
Well x-2y=1 is the equation of one line, so the points that satisfy the equation are exactly points on the line.
If you have two lines, then the points that satisfy both equations are points that lie on the two lines, i.e. where the intersection of the lines is.
how is that a line?
doesnt a line follow
y=mx+b
It's the same equation as y = -x/2 -1/2
In general the equation ax + by = c is the equation of a line.
You can solve for y
In terms of x
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A square based pyramid has coordinates A(4,0,2), B(-1,3,2), C(1,-5,2), and D. The apex lies directly above the centre of the base, and the pyramid has surface area 210 units^2.
a)Find the coordinates of D.
b)Find the height of the pyramid, correct to 1 decimal place
c) Hence find the volume of the pyramid
what have you done so far?
theres no working, but i figured out (or think so) that D has the coordinates (4,5,2)
and the apex (0,-1,h), where h is height
From there, i thought that since they gave us the surface area, it would have something to do with the height, but it doesn't
i think you can find h if you use the formula for the surface area, A=2bs+b^2
where b is the length of the base
because this is a pyramid, you take the slanted height, making my hypothesis useless
but the slant height is just pythagoras isnt it?
we've not been taught the surface area formula
we have to find the area of the base, and then the 4 triangular faces, and add them up
it is?
imagine a triangle that is between the midpoint of AB, the apex, and the point on the base directly below the apex
i think thats a right angled triangle
so ur saying that if i take the midpoint of AC and AD, then the midpoint of AD will be directly below the apex, meaning that the slope of the midpoint AC is a perpendicular bisector of the other midpoint?
so then if i find the distance of the two midpoints, i will have the short leg, and thus will be able to calculate the height?
I dont think so, because to do that, I will need the coordinates of the height itself to figure it out
someone help me please
how do i find the height, it could be literally anything
what happened man
why you leave me
:(
no im trying to figure something out, im not sure your coordinates for D are correct
they were posting mrbeast crypto scam again probably
oh
idk either
NOO??
idk i saw 4 images and they were the same colour scheme as the scam thats been popping up all day
anyway @glass edge are you sure your coordinates for D are correct?
i think so yeah
IT WASN'T ME, I JS DELETED BC MY PFP WASN'T WORKING
plot just the x and y into desmos, you get this https://www.desmos.com/calculator/td57vzgu9d
thats x and y tho
not x,y, and z
all z are 2 though
but A(4,0,2) was 2?
oh 
no the pyrmaid base is slightly rotated ibelive so ucannot graph it on 2d
-# i feel like this might be wrong but i am not sure
what makes you not sure?
-# why are you speaking in small text
-# because i am not sure
because there is no evidence to go off off
they're soft spoken don't mind it
you couldve said it in normal, and it would have the same meaning though, right?
ok
(nvm ignore this i just realizei am wrong lol)
sorry
oh so we're js guessing atp okay 💀
..
okay so just to confirm the pyrmaid base has to be asqaure correct?
it's still 3d pyramid, i think it's right
thats why im asking for help here
actually u are correc this is a correct plot btw i was wrong ^
square bottom, four sides go into one point
no need to be so rude lmao
Oh wait
it was a joke chill 😭
okay i am sure THat d has a diffrent answer-
okay oaky so look at it this way
u have 3 points! we know thier location
yes
and we know between each angle it must form 90 degrees correct?
no..?
why would it
yes
okay and we know that in total we have 360 degrees
so that must mean that each angle is?
i havent been taught that
okay okay lets visualize it then!
yeah, im pretty bad at visualizing 3d
dw we dont need any 3d for now!
okay
how many angels does it have?
(ignore the fact that i highlighted and extra angle on the bottom right)
total 360
okay makes sense so far
so what is a base of a pyrmaid made of?
not the area- i mean the angels in the the base of the pyrmaid
or BC*BD
oh
90 degrees again?
it is made of rectangle or a square correct?
okay visualze a pyrmaid anypyrmaid and look at it from the bottom
what would u see?
oh yeah, and then a rectangle would have 90 degrees to
YUP!
a rectangle/square base
okay so know lets look at the 3 point u graphed!
we should find one that form 90 degrees with the others correct?
yes
kinda of like this in a square
okay so since right now we are doing the base and only the base-
yeah, but mine is more of a rectangle, two sides are 8, and the other 5
can u now try to find where D coul possible be?
this is a top down prespective from ur graph
(i just removed the D)
look at this
which point here forms 90 degrees with the others?
u see the distance from the red point to the green point over there
its an x amount of right and y amount of down right
i applied the same thing to the grey one above
thinking i would get D
but this is 3d
so it didnt work
okay okay so first things off-
dont worry its not 3d yes we have 3 cordinates bet let me show u something really cool
when i look at it from the side they all have 0 hieght
which means we can go ahead and say that they are all on the same plane-
so for our concerns we only need x and y
does that make sense?
grey being C (1,-5,2) right?
(think of it as kind of writing on paper? if everything is on paper does ur pen ever need to right in 3d?
4,5,2
yes
but when i draw it on paper, it looks like this
okay so go ahead and move the graph so its from a perfect side perpspective
giving me impressions of different heights
do u see any points having diffrent hieghts?
yup yup BUT u need to rotate it around!
wait are you talking about your presumed idea of where D is?
this seems like a discrepancy oh no
now lower it a bit so its perfectly from the side and it will look like ^
ofc, i have no idea where even the apex is
||dw ik where D is its pretty easy to figure out but iam trying to explain it to them||
okay if u dont trust me hjere is my proff
notice how every point so far has an ending with 2 (aka its location on the Z axis)
that means that they all have the same hieght
correct?
based off this model, the d point is actually blue though?
well, but the thing is i want to find D consistently. not just this problem, which will be hard
yes
i found that out, which is why i know for sure that z is 2
@dusk halo don't stay mysterious where r u
yes i am just trying to first to get you to unerstand diemnsions
i found x to be 4 because the distance from A to C is 4, and the other points are parallel
okay since we know we can ignore the Z axis we can look at this from a 2d prespective
okay
but im scared of all the times we cant do it
but okay
look if you undertand how to do something in 2d first then ucan do it in 3d later on
yeah and we already understand that the z coordinate will be 2 because they're on the z plane
so first things off we would need to choose a point to translate into the fourth corner
i am going to use this example
assuming we choose point (top right purple)do u have an idea how we could translate it to the point we want?
,w A square based pyramid has coordinates A(4,0,2), B(-1,3,2), C(1,-5,2), and D. The apex lies directly above the centre of the base, and the pyramid has surface area 210 units^2. Find the coordinates of D.
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by using the distance from blue to red
and applying it to purple
okay perfect! lets apply that to our example!
but Notice something important we had to use the purple point or red point as our refrence becaue what would happen if we had choosen blue point?
i chose the blue point.
i dont see whats wrong with using blue
and i applied the same to this question
well lets use blue! if i move it downwards one where do i end up?
but iwant to be in the corner to form a square..
so this is ocunter intutive right?
ohh
its much easeir to chose pruple or red since they are the "edge" points if that makes sense
yes
but how do we determine in our graph earlier which point is blue(aka the one we cant/shouldnt use)?
no but i think of it like this: the translation from blue to red is 1, and since blue is parallel to purple, then if i move purple down 1, it will have the same result
its complementary to point D
yes but u will end up 1 to the left too muhc- which means to use blue point u will need to first move 1 down and then 1 to the right to complete the square
does that make sense?
yes
okay so knowing this infomration we can go ahead and look at our 3 points up here in 2d can u try to determine which point we Shouldnt/harder to use?
no cuz u start from purple
and then go down
if u use purple as the starting point then all is good!
okay okay lets just move on
-# bassicly what i am trying to say is the point opposite the point we want will require double trasnlation
yea
okay so looking at this
we shouldnt use red
anyways know knowing the cordinates we can go ahead and find the diffrent from A to B and apply that To point C so we get point D
does that make sense?
what is left to be found
yes
(i meant as in the desmos graph u sent earlier)
okay go for it! you got this!
point D aka the fourth point in the sqaure / rectangle
the d coordinate
oh
i am just trying to get Tan to solve it i think he got it now!
distance from a to c for x is 5
so x =5
distance from c to b for y is 8
so AD =8
and y should be 8
and we know that z=2
D(5,8,2)
ah soo not quite.. i belive
3d is just not for me
lets look at this example one more time
look at the cordinats here-
what would u need to do to get purple point to its correct location-
how do u know the distance from purple to unknown
-# dw we are working in 2d here
corrected*
-# also asorry about hand writing
(0,1) and (0,0), delta y = 1
so should be the same for unknwon
(something,1)
(0,1) and (1,1), delta x =1
so i got the point D how i am supposed to explain that
uhh nope close but not quite right-
omg
so here is the thing..
(0,1)
yes that is correct!
okay so here is the thing
when u translate something..
we know that lines blue and red are parraler to purple and unknown correct?
yes
okay so we know that distance red to blue lets call that distand D
we know if we apply that to purple we get our forth point correct?
yes
okay so lets try to calulate the distance for this smple example here
how much is point A (blue) displaced by from point B (red)
reember that its displaced on both the (x and y) axis
sqrt5
okay when in graphs when i mean distance i dont mean actualy length ik u just used pythgerous therom-
i mean by how much should u dsiplace the y and then by how much the x
can i give my explanation to the forth point ?
to get to thesame point-
go ahead!
4 down 2 left
so you can see the red point in the pic i sent
so there's a pattern to every point
go three units down from red and 5 units to right you will get blue
same 3 units left from blue and 5 units down you will get green
and for D
-# this is correct btw well done and for refrence leftand right is x and up and down is y so u would translate the point by -2 for x and -4 for why
do you undertand tan?
go three units down from red and 5 units to right you will get blue
same 3 units left from blue and 5 units down you will get green
what same 3 units?? you went RIGHT before 5 UNITs, not left 3
-# great explination btw i just think tan doesnt understand translation on graphs yet...
i also havnt studied 3d geometry yet so i see it in 2 d
and then u went up, left, and anywhere else
-# the entire first half of the question is 2d anyways no worries
okay oaky tan
lets focus on one thing at time-
first do u undertand how to move a point in graphs
for example wahat happens if i add 2 to x of a cordinat of (2,4)
hey no you houldnt please dont!
its okay to take a break sometime
ik ik sorry- this is just a pre for a folow up question
sorry
okay can u visualize it happening on a graph?
yes
oaky what if it was something more complicated though lets say we want to move it a distance of 5 for x and 2 for y
you can eat n do work yk 😭
it would move kinda of like in a daignoal correct?
(7,6)
(i want you to visualize it)
(without me having to do the diagram)
yes most important thing here is visualization becasue i want you to intutively understand this i could jsut give u a formula and go- but these concept will be realyl important later on)
i imagine a stair going right 5 and up 2
from 2,4
okay okay i guess that works butwhat if u made that stair really smooth-
almost like a ramp
can usee it now?
i -
oh
wait lets plot it
ues
okay makes sense right?
yes
okay now take this graph
i want u to imagne applying that line we had from red to grey
onto the green ball
||nope i amstil ltrying to explain it i think he is having trouble with graphs and trasnlation||
can u vissiliaze it tan?
IOKAY nice nice nice!
okay wait let me get u an SS with the graph poitning in the right ridrection cause its rotated
okay so looking at this point-
can u try to do what u just did with the green point
yup yup
so know do u understand how u can solve it?
A square based pyramid has coordinates A(4,0,2), B(-1,3,2), C(1,-5,2), and D. The apex lies directly above the centre of the base, and the pyramid has surface area 210 units^2.
a)Find the coordinates of D.
lets look at this (4,0) and (-1,3) , and (1,-5)
can u now using this infomration find point D?
since in my case c is oppposite of d, translate c to a and do the same using b as starting point
YUP!
and then calculat the cordinates!
1 to 4 is left 3, and -5 to 0 is up 5
so i should go right 3 and down 5
starting from b
uh huh
right 3 from b would give us 2
as x value
an
d
8 as y value
D(2,8,2)
nope
its down 5
D(2,-2,2)
okay oaky but wait a moment-
does 1 to 4 gives us 3 or maybe ?
3
remeber u started from point (4.0) right? and drew the line to point (1,-5)
ah
-# come on you got this!
if i start from the 4th tile and i end up on the first tile how much did i move
consideing the more i go to the right the higher x i have
3 left
negative
D(-2,-2,2)
-# why did u chagne the y value?
the y value was always negaitve
no no let them figure it out
tan dont look at this spoiler||wait anmol the answer is (-4,-2,2) right?||
oaky regarding the X
the point we used at refrence
ive come to the realization that i am egregious at understanding math. I think my best option is to stick to memorizing formulas and when to use them
at what cordinate did it start tan-
NO NO
wait WAIT
UR SO CLOSE-
that it how i can make real progress
wait
this is too slow
UR LITTERLY RIGHT THERE
u just made 1 tiny mistake-
can u remind me of point B cordinates
it was (-1,3,2)
correct
so waht happens wehn u do -1 -3 ?
but at what cost
ive lost over a hour and half
i couldve spent on memorizing formulas and when to use them
-4
okay well the answer is going to ||(-4,-2,2)|| the reasn its ||-4|| is because B actually start at ||-1|| not ||1|| as u calculatedearlier
there you go!
thats the asnwer-
do u understand now where the answer came from-
oh well I got a different answer uhh
pleae go eat dinner and take some rest u have done well-
wait wha- what did u get?
nope..
the only thing i can think of is that the point A has x coordinate 4, and D is in the same x line as A
||D = (6, -8, 2) ||(tan don't look)
no point now its 9pm, ill just finish this worksheet ( or try to) and sleep
bye bye
sorry- i wish u best of luck..
its not ur fault its mine
||the question says it must be a square this i belive is aparrelrogram||
.close
Closed by @glass edge
Use .reopen if this was a mistake.
personally, i think its a rectangle
me too
point (-4,-2,2) makes it a square i belive..
naturally yeah
also the q says "A square based pyramid has coordinates"
ur right
its not about it looking exactly like a square though, it won't be a perfect square with a right angle everytime 😭
its okay i am tan you should be proud for triying! ihope maybe one day some of this explination can help you somehow for now rest and i wis u best of luck!!
WAIT SO THEN ALL SIDES ARE SAME HOW DID I GET 8 AS TWO SIDES AND 5 AS THE OTHER
count each ttrasnlation from each point its the same number.. therfore its 90 degrees at each corner
gn!
umm
can't say
but the vector rule is D = A + (C − B)?
-# i think iam gonna go rest aswell for a bit thanks for the graph earlier anmol
no problem
ask me i am always here
you here to for my help
i should mention here that point A is not and Edge point it is at the corner Opposite of where we actually want to be which is why this Q is so confusing
because point A is between Point B and C if that makes sense
it's not that confusing gng 💔
well to some it is..
wdym by that
but idk i may be wrong anmol opnoins on this?
okay so the 3 points here Point A is the red and as u can see it is on the opposite corner of where we want to be-
remeber square = 90 Degrees so there is no other possiblity of any other points bieng the corner other than A

