SOLUTION: Factor the trinomial. b^3-2b^2-63b

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Question 229599: Factor the trinomial.
b^3-2b^2-63b
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor:
b%5E3-2b%5E2-63b First, since each term has common factor of b, a b can be factored.
b%28b%5E2-2b-63%29
Now look at the constant term (-63) and see what its factors are:
-63+=+3%28-21%29
-63+=+-3%2821%29
-63+=+7%28-9%29
-63+=+-7%289%29
Now you need the pair of factors from the above list whose sum is -2 (the coefficient of the center term of the trinomial.
A quick look will show that the pair that meets this requirement is 7%28-9%29 because 7%2B%28-9%29+=+-2. Now you can finish the factoring process.
highlight%28b%5E3-2b%5E2-63b+=+b%28b%2B7%29%28b-9%29%29