Question

Which is the equation of a parabola with Vertex (0,0) and directrix x=-2?

Answer 1

y^2 = 8x

or

x = 1/8 y^2.

Explanation:

The general form for this type of parabola is

y^2 = 4ax where the focus is at (a, 0) and the directrix is x = -a

So the equation is y^2 = 4*2x

that is y^2 = 8x.