IN GENERAL:
When you have trouble factoring a polynomial of degree 2 with a coefficient different from in front of ,
you can split the term in into two terms, and factor by parts,
like this: .
To find how to split the term in ,
look for factors of the product of the other two coefficients
(in this case, factors of ).
Look for a pair that adds up to the coefficient of ,
and when multiplied gives the product of the other two coefficients.
In this case and .
