SOLUTION: Solve x^2-8x+15 by completing the square and quadratic formula

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Question 745098: Solve x^2-8x+15 by completing the square and quadratic formula
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve x^2-8x+15 by completing the square
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x^2-8x+? = -15+?
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x^2 -8x + 16 = -15+16
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(x-4)^2 = 1
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x-4 = 1 or x-4 = -1
x = 5 or x = 3
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and quadratic formula
x = [8 +- sqrt(64-4*1*15)]/2
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x = [8 +- sqrt(4)]/2
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x = [8+-2]/2
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x = 5 or x = 3
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Cheers,
Stan H.
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