Answer:
f(x) = (x - 5)^2 + 4.
Step-by-step explanation:
The vertex form of a parabola is
f(x) = a(x - h)^2 + k where the vertex is at (h, k) and a is some constant.
So here we have:
f(x) = a(x - 5)^2 + 4
Now when x = -1 , f(x) is 40 so:
40 = a(-1-5)^2 + 4
36a = 40 - 4 = 36
a = 1.
So the function is f(x) = (x - 5)^2 + 4