SOLUTION: Find the axis of symmetry. y = x² - x + 5

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Question 173359: Find the axis of symmetry.
y = x² - x + 5
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

To find the axis of symmetry, use this formula: x=%28-b%29%2F%282a%29.


x=%28-b%29%2F%282a%29 Start with the given formula.


From y=x%5E2-x%2B5, we can see that a=1, b=-1, and c=5.


x=%28-%28-1%29%29%2F%282%281%29%29 Plug in a=1 and b=-1.


x=%281%29%2F%282%281%29%29 Negate -1 to get 1.


x=%281%29%2F%282%29 Multiply 2 and 1 to get 2.


So the axis of symmetry is x=1%2F2.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the axis of symmetry.
y = x² - x + 5
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There are at least two ways:
1st: x = -b/2a = 1/2
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2nd: Complete the square:
x^2-x + ? = y-5 + ?
x^2 -x + (1/2)^2 = y - 5 + (1/2)^2
(x-(1/2))^2 = y -20/4 + 1/4
(x-(1/2)^2 = y-(19/4)
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Axis of symmetry: x = 1/2
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Obviously the 1st way is the quickest way to find the axis of symmetry.
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Cheers,
Stan H.