Question

Which equation represents the axis of symmetry of the function y=-2x^2+4x-6.

Answer 1

Your  answer is x = 3

Answer 2

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

You have
  a = -2, b = 4
so
  x = -b/(2a) = -4/(-2*2)
  x = 1

The appropriate choice is
  b. x= 1