SOLUTION: Find the vertex of the parabola. f(x) = -x2 + 9x - 5

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Question 358370: Find the vertex of the parabola.
f(x) = -x2 + 9x - 5
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The coordinates of the vertex are x+=+-b%2F2a, and y+=+%284ac-b%5E2%29%2F%284a%29. Thus x+=+-9%2F2%28-1%29+=+9%2F2, and y+=+%284%28-1%29%28-5%29-9%5E2%29%2F%284%2A%28-1%29%29=61%2F4.