http://www.mathwords.com/d/directrix_parabola.htm

The link defines a directrix compared to a focus.

Thus, the vertex would still be at the same axis of symmetry, which is x=-5

and your y would be directly between -5 and 7, so, y=1. Because the directrix is above the focus, the parabola points down. so a=-a.

y=a(x-h)^2+k

a has to be negative because the parabola points downward.

the vertex is (h,k) -----> (-5, 1)

y=-a(x+5)+1

So the answer has to be C, the third option.

Hope that helps (:

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