Question

−12x2 − 28x + 80 = 0

Answer 1

-12*2 - 28x +80=0
-24 - 28x + 80= 0
-28x + 56 = 0
56 = 28x
x=2

Answer 2

thank you!

Answer 3

I think @beccal703 misunderstood the problem.

−12x2 − 28x + 80 = 0
I think you mean
−12x^2 − 28x + 80 = 0
First divide both sides by -4
3x^2 + 7x - 20 = 0
Now factor the left side:
(3x - 5)(x + 4) = 0
3x - 5 = 0 or x + 4 = 0
3x = 5 or x = -4
x = 5/3 or x = -4