SOLUTION: what is the equation of a parabola whose vertex is the origin and whose directrix is the line y=-3?

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Question 24554: what is the equation of a parabola whose vertex is the origin and whose directrix is the line y=-3?
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
THE GENERAL EQN. OF PARABOLA WITH VERTEX AT ORIGIN IS GIVEN BY
Y^2=4AX.....WHERE DIRECTRIX IS GIVEN BY
Y+A=0.....WHICH IS GIVEN AS Y=-3..OR...Y+3=0...OR A=3
HENCE
EQN.OF PARABOLA IS
Y^2=4*3*X=12X