If x is real, find the maximum value of the expression -2x^2 + 5x + 7. Pick one
A) 6.125
B) 8.125
C) 10.125
D) 12.125
E) 14.125
This is an equation of a downward facing parabola.   The maximum value is the top point of the parabola.   -2x^2+5x+7 = (-2x+7)(x+1)   The roots are 7/2 and -1.   The maximum value must be when x is halfway between these two points.   x = 1.25   The maximum value is -2(1.25)^2+5(1.25)+7 = 10.125   The answer is 10.125.
<result>C</result>
If x is real, find the maximum value of the expression -2x^2 + 5x + 7.