SOLUTION: Please help Find the axis of symmetry for.... y = x^2 – 9x + 3

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Question 185700: Please help Find the axis of symmetry for....
y = x^2 – 9x + 3

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the axis of symmetry for....
y = x^2 – 9x + 3
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complete the square on the x-terms:
x^2 - 9x + ? = y-3+?
x^2 - 9x + (9/2)^2 = y - 3 + (9/2)^2
(x-(9/2))^2 = y -12/4 + 81/4
(x-(9/2))^2 = y+(69/4)
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Axis of symmetry: x = 9/2
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You could get the same answer as x = -b/2a = -(-9/2*1) = 9/2
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Cheers,
Stan H.