Question

What are the solutions of x^2 + 8x − 20 = 0? Show all work for full credit.

Answer 1

To solve
x^2 + 8x − 20 = 0
I would factor it
to find the factors:
first, notice the -20, that means the two factors will be opposite signs
second, the +8 (on the x term) means the larger factor is plus

third, list the factors of 20
1,20
2,10
4,5

does any pair when subtracted give us +8?
if so, that is the pair to use :
(x-2)(x+10)= 0

now solve for x: either x-2=0 or x+10=0

Answer 2

x^2+10x-2x-20=0
x(x+10)-2(x+10)=0
(x+10)(x-2)=0

either or
x+10=0 x-2=0
x=-10 x=2