Question

Solve the equation using factoring. x2 + 8x - 20 = 0
Anwsers:
{-2, -10}
{2, 10}
{-2, 10}
{2, -10

Answer 1

Find the two numbers that multiply to -20, and add to +8.

Answer 2

i think i got it...-2, 10?

Answer 3

But then that represents (x-2)(x+10) = x^2 + 8x - 20, so we aren't done yet.

Answer 4

aww. no more medals for wrong answers?

Answer 5

Then we need to solve x-2 = 0, and x+10 = 0

Answer 6

yes.. they try lol

Answer 7

I can assure you is one of those ;D keep thinking :p

Answer 8

@dpaInc LOL , I would vote for the quadratic equation formula, it always works!

\[\Large x_{1/2}=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\]
in your case you have to substitute ...
a=1
b=8
c=-20

calculate , and there's nothing else to get confused O_O

Answer 9

that is definitely right...