How do you find the axis of symmetry?

x=-b/2a

Step-by-step explanation:

axis of symmetry is the line that across the vertex from a parabola(ax^2+bx+c).

The expression to find vertex is -b/2a

Thus, x=-b/2a is a vertical line that across the vertex aka the axis of symmetry.

47 - 90 = 43

43 - 180 = x

x = 137