SOLUTION: Find the vertex, focus, and directrix of the parabola given by the equation (x-9)^2=-(y+8)?

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Question 201741: Find the vertex, focus, and directrix of the parabola given by the equation (x-9)^2=-(y+8)?
Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
(x-9)^2 = - (y+8)
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(y+8)= -1 (x-9)^2,,,,,form (y-k) =A (x-h)^2
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h=9,,k=-8,,,,or vertex (9,-8)
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A= -1,,,therefore pointed down
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basic form 4p = A,,4p =1, p=1/4
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focus is at (-8 -1/4) = -8.25,,,,or (9,-8.25)
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diectrix is at y= ( -8 +1/4),,,y = - 7.75