Answer:
(1, -16)
Step-by-step explanation:
The line of symmetry is halfway between the x-intercepts, at ...
x = (-3 +5)/2 = 1
The line of symmetry goes through the vertex, so to find the y-coordinate of the vertex, we need to find f(1):
f(1) = 1^2 -2(1) -15 = -16
The vertex of the function is (x, y) = (1, -16).
