SOLUTION: (x − 1)^2 = 12(y + 5) what is the vertex, focus, and directrix?

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Question 678079: (x − 1)^2 = 12(y + 5) what is the vertex, focus, and directrix?
Answer by lwsshak3(11628) About Me  (Show Source):
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(x − 1)^2 = 12(y + 5) what is the vertex, focus, and directrix?
This is an equation of a parabola that opens upwards.
Its standard form: (x-h)^2=4p(y-k), (h,k)=(x,y) coordinates of the vertex
For given equation:(x−1)^2 = 12(y+5)
vertex: (1,-5)
axis of symmetry: x=1
4p=12
p=3
focus:(1,-5+p)=(1,-5+3)=(1,-2) (p units above vertex on the axis of symmetry)
directrix: y=-8 (p units below vertex on the axis of symmetry)