SOLUTION: Can someone show me how this is done please .Thanks Write f(x)=-9x^2+18x in standard form.

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Question 739378: Can someone show me how this is done please .Thanks
Write f(x)=-9x^2+18x in standard form.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Write f(x)=-9x^2+18x in standard form.
complete the square:
f%28x%29=-9%28x%5E2-2x%2B1%29%2B9
f%28x%29=-9%28x-1%29%5E2%2B9
This is an equation of a parabola that opens downward.
Its standard form: y=-A%28x-h%29%5E2%2Bk, (h,k)=(x,y) coordinates of the vertex, A is a coefficient that affects the slope or steepness of the curve.
For given equation:
vertex:(1,9)