Question

Question #35634

Answer 1

`x=10`

Explanation:

I think you meant to write `y = 3(x-10)^2 - 9`.

The equation of this parabola is in vertex form: `y = a(x-h)^2 + k`, where `(h,k)` is the vertex. In this case, `(10, -9)` is the vertex.

The axis of symmetry of a parabola is the line that divides the parabola in two and runs through the vertex. The axis of symmetry is represented by the line `x=h`. So, the axis of symmetry here is `x=10`.

graph{y=3(x-10)^2 - 9 [-10, 30, -12, 12]}