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
