SOLUTION: Write an equation for the parabola with focus (4,0) and directrix y=2. Thanks!

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Question 458635: Write an equation for the parabola with focus (4,0) and directrix y=2.
Thanks!
Answer by lwsshak3(11628) About Me  (Show Source):
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Write an equation for the parabola with focus (4,0) and directrix y=2.
Thanks!
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Standard form of parabola: (x-h)^2=4p(y-k), with (h,k) being the (x,y) coordinates of the vertex
Given parabola opens downward with axis of symmetry at x=4. Vertex at (4,1). p=1
Equation of parabola:
(x-4)^2=-4(y-1) (ans)
see the graph below as a visual check on the answer
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y=1-(x-4)^2/4
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+1-%28x-4%29%5E2%2F4%29+