Question

hey can someone help me with 8 math questions on parabola? THANK YOU SO MUCH

Answer 1

@DanJS can u help?

Answer 2

yeah, it looks like they want you to put each one in the form at the top...

Answer 3

ya

Answer 4

-2x^2 = 16y

put that into the form at the top

Answer 5

i kinda need help

Answer 6

@zepdrix @triciaal

Answer 7

do you want to know how that equation is made, where it comes from, or just how to use it ?

Answer 8

To just use the thing, solve the problem for y first

-2x^2=16y
\[\large y=\frac{ -1 }{ 8 }x^2\]

look at the form of the equation..
\[\large y=\frac{ 1 }{ 4p }(x-h)^2+k\]
vertex- (h,k)
focus - (h, k+p)
directrix- y=k-p

Answer 9

if you want you can fill in the zeros to make it look the same

\[y=\frac{ -1 }{ 8 }(x-0)^2+0\]

Answer 10

Reading from the equation, the -1/8 is the same as the 1/(4p), so
\[\frac{ -1 }{ 8 }=\frac{ 1 }{ 4p }\]
p=-2

Answer 11

Then just read the values from the equation..
vertex (h,k) = (0,0)
focus (h,k+p) = (0,-2)
directrix - (h, k-p) = (0,2)

Answer 12

I would find the x and y axis intercepts (0,y), (x,0) to use for points to graph, then also the vertex point. Here only intercepts are (0,0).