Write an equation of a parabola that opens to the left, has a vertex at the origin, and a focus at (–9, 0).

Question

A) y=(-1/16)x^2 B) x=(-1/36)y^2 C) x=(-1/16)y^2 D) y=(-1/24)x^2

Answer 1

a=-9, h=k=0

x = a(y - k)² + h 

x = -9 y^2