Step-by-step explanation:
General equation of a parabola parallel to the x-axis: (y - k)^2 = 4p(x - h).
Vertex = (h, k) = (0, 0)
Directrix: x = h - p = -2.
Since h and k are 0, p must be 2.
Therefore the equation is y^2 = 8x.
