SOLUTION: Find the axis of symmetry: Y= x^2 + 7x + 10 ASm I suppose to find out what x equals?? Or I am just suppose to find a solution to the problem? Thank you

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Question 70089: Find the axis of symmetry:
Y= x^2 + 7x + 10
ASm I suppose to find out what x equals?? Or I am just suppose to find a solution to the problem? Thank you

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the axis of symmetry:
Y= x^2 + 7x + 10
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You need to put the quadratic in vertex form by completing the square.
This is vertex form: y-k=(x-h)^2 where (h,k) is the vertex. x=h is
then the axis of symmetry.
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Rewrite the equation as:
y-10 = x^2+7x
Complete the square on the right side and keep the equation balanced:
y-10+(7/2)^2 = x^2+7x+(7/2)^2
Factor the right side; simplify the left side:
y-10+49/4 = (x+(7/2))^2
y+(9/4) = (x+(7/2))^2
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So, -h=7/2
h=-7/2
x=-7/2 is the axis of symmetry
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Here is the graph so you can see the axis of symmetry:
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2Cx%5E2%2B7x%2B10%29
Cheers,
Stan H.