Answer:
f(x) = x^2 -2x -8
Step-by-step explanation:
(x+2)(x-4)
FOIL
first: x*x = x^2
outer: -4x
inner: 2x
last: 2*-4x = -8
Add together
x^2 +2x-4x-8
x^2 -2x -8
This is a parabola
