SOLUTION: y=-(x-1)2 -4 find p, axis of symmetry, veritces, foci, directix for this parabola. Thank-you!

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Question 132351: y=-(x-1)2 -4
find p, axis of symmetry, veritces, foci, directix for this parabola. Thank-you!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
y=-(x-1)2 -4
find p, axis of symmetry, vertices, foci, directrix for this parabola. Thank-you!
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Rewrite as (x-1)^2 = (y+4)
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4p=1; p = 1/4
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Axis of symmetry: x = 1
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Vertex: (1,-4)
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focus: (1,-4+1/4) or (1 , -15/4)
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directrix: y = -4-(1/4) = -17/4
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graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C%28x-1%29%5E2-4%29
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Cheers,
Stan H.