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Find the equation of the parabola with focus $\ (6,0) $ and directrix $\ x=0 $


What I have done so far:

$ (x-h)^2 = 4p(y-k) $

$ (h,k) = (3,0) $

$ (x-3)^2 = 12y $ as p = 3

However, the answer shows that it's $ y^2=12x-36 $

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The right side should be squared and not the left side just look at the directrix –  user10444 Jan 6 '13 at 21:03

1 Answer 1

up vote 1 down vote accepted

When you start with $(x-h)^2 = 4p(y-k)$, you presuppose that the parabola is vertical. But here, the directrix is vertical, and so the parabola is horizontal.

Does this give you the next step?

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