derive the equation of the parabola with a focus at (-5, 5) and a directrix of y = -1.

A. f(x) = -1/12 (x - 5)^2 + 2

B. f(x) = 1/12 (x - 5)^2 + 2

C. f(x) = -1/12 (x + 5)^2 + 2

D. f(x) = 1/12 (x + 5)^2 + 2