The focus of a parabola is (4,7) and the directrix is y=8.
What is an equation of the parabola?
A: (x−4)^2=−(y−9)
B: (x−4)^2=−4(y−9)
C: (x−4)^2=−2(y−7.5)
D: (x−4)^2=−0.5(y−7.5)
p = - 1/2......so the equation is
4p(y-7.5) = (x - 4)^2
-2(y - 7.5) = (x - 4)^2 .........."C" is correct
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