Factoring – Grouping Method Sometimes there is not a common factor other than 1 for the expression. But when the terms are put into groups, there may be common factors. This suggests the method called factoring by grouping. Whenever an expression contains four terms, this is a good method to consider.

Example 1: Notice that there are four terms, and that the greatest common factor is 1. Write the polynomial into two groups:

Factor each binomial. Factor out the common binomial factor

Example 2: Notice that there are four terms, and that the greatest common factor is 1. In this case, neither the first pair nor the last pair of terms have a common factor. Sometimes it is necessary to change the order of the terms.

Group the terms into two binomials: Move the second term to the end:

Factor each binomial. Factor out the common binomial factor