Question 464378
Find the vertex, the line of symmetry, the maximum or minimum of the quadratic function, and graph the function: 
f(x)=-2x^2+2x+8
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standard form for parabola: y=(x-h)^2+k, (h,k) being the (x,y) coordinates of the vertex.
for given equation:
y=-2x^2+2x+8
completing the square
y=-2(x^2-x+1/4)+8+1/2
y=-(x-1/2)^2+17/2
This is a parabola that opens downward, with vertex at (1/2,17/2).
Axis of symmetry: x=1/2, maximum=17/2
See graph below as a visual check on answers:

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{{{ graph( 300, 200, -4, 4, -10, 10,-2x^2+2x+8) }}}