SOLUTION: I need help to find the vertex, focus, and the directix of this parabola problem: y^2 – 12y + 16 – 20x = 0

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Question 468949: I need help to find the vertex, focus, and the directix of this parabola problem: y^2 – 12y + 16 – 20x = 0


Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What sort of help?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I need help to find the vertex, focus, and the directix of this parabola problem: y^2 – 12y + 16 – 20x = 0
20x = y^2-12y+16
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Complete the square:
y^2-12y+36 = 20x-16+20
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(y-6)^2 = 20x+4
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20x = (y-6)^2-4
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x = (1/20)(y-6)^2 - (1/5)
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Vertex at (-1/5,6)
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4p = 1/20
p = 1/80
Directrix: x = -1/5-1/80 = -17/80
Focus: ((-1/5+(1/80),6) = ((-15/80),6)
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cheers,
Stan H.