SOLUTION: factor the polynomials. x^2+ x-20

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Question 213941: factor the polynomials.
x^2+ x-20
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Factor the polynomials.

x%5E2%2B+x-20=%28x%2B5%29%2A%28x-4%29

Note we need to find two numbers A and B such that A*B=-20 and A+B=1. After trial and error like A=1, B=-20 or A=2 and B=-20 the numbers that satisfy these relationships are A=5 and B=-4.

where x%5E2%2Bx-20=x%5E2%2B%28A%2BB%29x%2BA%2AB.

We can check our factoring by using the FOIL method as well.

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J