Chapter 6 - Factoring, Solving Equations, and Problem Solving - 6.5 - Factoring, Solving Equations, and Problem Solving - Problem Set 6.5 - Page 270: 101

The answer is below.

While it is not necessary, looking for the greatest common monomial factor is useful because it makes the expression more simple (by making the numbers less large). This is helpful as factoring is a matter of guessing and checking, so reducing the size of the numbers largely reduces the amount of effort it takes to solve for the factor.