SOLUTION: Find the equation of the parabola with its vertex at the origin if its directrix is y=3

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Question 449573: Find the equation of the parabola with its vertex at the origin if its directrix is y=3
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
As you know the directrix of the parabola x%5E2=4cy is y=-c, since y=3, we get
3=-c or c=-3, and the equation of parabola will be: x%5E2=-12y.
graph%28300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+%28-1%2F12%29%2Ax%5E2%29.