1. Learning Targets
Students will be able to: Choose an appropriate method for factoring a polynomial and combine methods for factoring a polynomial.
Recall that a polynomial is in its fully factored form when it is written as a product that cannot be factored further.
x2 + 4 is a sum of squares, and cannot be factored.
Caution

2. To factor a polynomial completely, you may need to use more than one factoring method. Use the steps below to factor a polynomial completely.

3. If none of the factoring methods work, the polynomial is said to be unfactorable.
For a polynomial of the form ax2 + bx + c, if there are no numbers whose sum is b and whose product is ac, then the polynomial is unfactorable.
Helpful Hint