Answer:
(-9, 0), (-1, 0)
Step-by-step explanation:
In vertex form, the equation of the parabola is ...
... f(x) = a(x +5)^2 +80
Then f(0) = -45 = a(5)^2 +80
... a = -125/25 = -5
Since we want the x-intercepts, we want the solutions to ...
... -5(x +5)^2 +80 = 0
... (x +5)^2 -16 = 0 . . . . . divide by -5
... x + 5 = ±√16 . . . . . . . add 16 and take the square root
... x = -5 ± 4 . . . . . . . . . . subtract 5
... x ∈ {-9, -1}
So the coordinates of the x-intercepts are (-9, 0) and (-1, 0).