SOLUTION: what is the directx of 8x=y^2

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Question 467998: what is the directx of 8x=y^2
Answer by lwsshak3(11628) About Me  (Show Source):
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what is the directrix of 8x=y^2
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Standard form for given parabola; (y-k)^2=4p(x-h), with (h,k) being the (x,y) coordinates of the vertex.
For given parabola: y^2=8x
vertex is at origin (0,0), parabola opens rightwards
4p=8
p=4
Directrix is a vertical line 4 units from the vertex at x=-4
see graph below as a visual check on answer
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y=±(8x)^.5
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%288x%29%5E.5%2C-%288x%29%5E.5%29+