Question

What is the vertex of the parabola with thefunction rule f(x) = 5(x − 4)² + 9?

Answer 1

The equation f(x) = a(x - h)^2 + k gives the vertex of the parabola--it is (h, k).

In this question, h = 4 and k = 9. So the vertex is at (4, 9).