the equation for the axis of symmetry for the graph of a quadratic function is x = –2. which of the following could not be the equation of the function?
a.
y=-2x^2-8x+3
b.
y=1/2x^2+2x-1
c.
y=4x^2-16x+2
d.
y=3x^2+12x

For
y=ax²+bx+c
the x value of the axis of symmetry is -b/(2a)

so test them

A., -b/(2a)=-(-8)/(2*-2)=8/-4=-2, yep
B. -b/(2a)=-2/(2*1/2)=-2/1=-2, yep
C. -b/(2a)=-(-16)/(2*4)=16/8=2, nope, need -2
D. -b/(2a)=-12/(2*3)=-12/6=-2, yep

answer is C