SOLUTION: How do I write x^2-16x+56=0 in vertex form? And, how do I identify the vertex?

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Question 281216: How do I write x^2-16x+56=0 in vertex form? And, how do I identify the vertex?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do I write x^2-16x+56 = y in vertex form? And, how do I identify the vertex?
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x^2-16x + ? = y -56 + ?
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x^2-16x + 64 = y-56+64
(x-8)^2 = y+8
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Vertex at (8,-8)
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Another Method:
y = x^2-16x+56
a = 1 ; b = -16
The vertex occurs where x = -b/2a = 16/-1 = 8
f(8) = 8^2 -16*8 + 56 = -8
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Notice the answers are the same.
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Cheers,
Stan H.