Question

Explain, in complete sentences, how to factor 5x2 - 5x - 30. Explain how your factors could be checked for accuracy.

Answer 1

5(x-3)(x+2)

Answer 2

First, I need to pull out the common factor, which is 5. this makes the equation \[5(x ^{2}-x-6)\]
then I have to find two factors of -6 that sum to -1.
Listing the factors:
-1 & 6
-2 & 3
-3 & 2 <--
This set of factors sum to -1. Placing these in the equation, the completely factorization is \[5(x-3)(x+2)\]
which we can check by using FOIL and multiplication.