1. 8.8 Factoring by Grouping

2. Factoring by grouping USE WHEN THERE ARE 4 TERMS IN THE POLYNOMIAL. Polynomials with four or more terms like 3xy – 21y + 5x – 35, can sometimes be factored by grouping terms of the polynomials. The key is to group the terms into binomials that can be factored using the distributive property. Then use the distributive property again with a binomial as the common factor.

3. Factor 3xy – 21y + 5x – 35 Group terms that have common monomial factor. Factor. Notice that (x – 7) is a common factor. Distributive property. Check by using FOIL.

4. Factor Group terms that have common monomial factor. Factor. Notice that (8mn - 5) is a common factor. Distributive property. Check by using FOIL.

5. Factor FOIL AND CHECK

6. Note: Recognizing binomials that are additive inverses is often helpful in factoring. For example, the binomials 3 – a and a – 3 are additive inverses since the sum of 3 – a and a – 3 is 0. Thus, 3 – a and –a +3 are equivalent. What is the additive inverse of 5 – y? -y + 5

7. Factor: FOIL AND CHECK (5-y) and (y-5) are additive inverses. (5-y)=(-1)(y-5)