SOLUTION: Find the equation of the parabola with vertex at origin and directrix as y+3=0

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Question 828973: Find the equation of the parabola with vertex at origin and directrix as y+3=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The standard form is %28x+-+h%29%5E2+=+4p+%28y+-+k%29 and the directrix is y+=+k+-+p.
The standard form of a parabola is:
%28x+-+h%29%5E2+=+4p+%28y+-+k%29
where (h,k) is the vertex.
x%5E2+=+4py
The directrix is
y+=+k+-+p=-3
0-p=-3
p=3
So then,
x%5E2+=+4py
x%5E2+=+12y
highlight%28y=%281%2F12%29x%5E2%29