SOLUTION: What is the directrix of the parabola represented by {{{ (y+4)^2=8(x-5) }}}

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Question 933222: What is the directrix of the parabola represented by +%28y%2B4%29%5E2=8%28x-5%29+
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
What is the directrix of the parabola represented by
+%28y%2B4%29%5E2=8%28x-5%29+
This is an equation of a parabola that opens rightward
Its basic form of equation: (y-k)^2=4p(x-h), (h,k)=coordinates of the vertex
For given equation:
vertex:(5,-4)
axis of symmetry: y=-4
4p=8
p=4
directrix: x=1 (p-distance left of vertex on the axis of symmetry)