SOLUTION: find the solution to the equation x^2+2x-8=0. I have x=-4,2 but I do not know if that answer is correct

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Question 81028: find the solution to the equation x^2+2x-8=0. I have x=-4,2 but I do not know if that answer is correct
Answer by tutor_paul(519) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B2x-8=0
The easiest way to solve this problem is to try factoring it. The equaltion is already set up being equal to zero, so you are good to go. Ask yourself "What are the factors of -8 that when combined give me 2 (the coefficient of x)?" Well, -2 and 4 definitely do, so try those as factors:
%28x-2%29%28x%2B4%29=0
If you multiply these factors out, you get your original equation back. So you know this has been factored correctly.
Now, since the product of these factors is equal to 0, each factor can be set up equal to zero and solved. then you get your 2 answers, or "roots."
x-2=0
highlight%28x=2%29
and
x%2B4=0
highlight%28x=-4%29
So you got it right!
Good Luck,
tutor_paul@yahoo.com