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Question 917446: I missed this lesson and am very confused with the problem. It says
Name the vertex, focus point, and directrix for the following equation:
x^2+8x-12y+64=0
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Name the vertex, focus point, and directrix for the following equation:
x^2+8x-12y+64=0
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12y = x^2 + 8x + 64
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12y = x^2 + 8x + 16 + 48
12y-48 = (x+4)^2
12(y-4)= (x+4)^2
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Vertex:: (-4,4)
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y-4 = (1/12)(x+4)^2
y = (1/12)(x+4)^2+4
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4p = 1/12
p = 1/48
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directgrix = y = 4-p = 4-1/48 = 191/48
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focus (-4,4+p) = (-4,(193/48))
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Cheers,
Stan H.
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