SOLUTION: FIND THE VERTEX THE LINE OF SYMMETRY THE MAXIMUM OR MINIMUM VALUES OF THE QUADRATIC FUNCTION F(X)=-X^2+10X+5

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Question 296384: FIND THE VERTEX THE LINE OF SYMMETRY THE MAXIMUM OR MINIMUM VALUES OF THE QUADRATIC FUNCTION F(X)=-X^2+10X+5
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29+=+-x%5E2+%2B+10x+%2B+5
When the sign of the squared term is minus, the
curve has a max and not a min.
The x co-ordinate of the max is always at
-b%2F2a
-b+=+-10
2a+=+-2
-10%2F%28-2%29+=+5
Now I need f%285%29
f%285%29+=+-5%5E2+%2B+10%2A5+%2B+5
f%285%29+=+-25+%2B+50+%2B+5
f%285%29+=+30 maximum
The line of symmetry is simply the x-value x+=+5
Here's a plot:
+graph%28+400%2C+400%2C+-5%2C+12%2C+-5%2C+35%2C+-x%5E2+%2B+10x+%2B+5%29+