1. Classwork: 01/23/17 1. 2(w + 1) 2. 3x(x2 – 4) 3. 4h2 and 6h Simplify.
Find the GCF of each pair of monomials.
3. 4h2 and 6h

2. Essential Questions
How do you factor polynomials by using the greatest common factor?

3. Aligning common factors can help you find the greatest common factor of two or more terms.
Writing Math

4. Example 1A: Factoring by Using the GCF
Factor each polynomial. Check your answer.
2x2 – 4
2x2 = 2  x  x
Find the GCF.
4 = 2  2 2
The GCF of 2x2 and 4 is 2.
2x2 – (2  2)
2(x2 – 2)
Check 2(x2 – 2)
The product is the original polynomial. 
2x2 – 4

5. Example: Factoring by Using the GCF
8x3 – 4x2 – 16x
8x3 = 2  2  2  x  x  x
Find the GCF.
4x2 = 2  2  x  x
16x = 2  2  2  2  x
The GCF of 8x3, 4x2, and 16x is 4x.
2  2  x = 4x
4x(2x2 – x – 4)
Check
4x(2x2 – x – 4)
The product is the original polynomials.
8x3 – 4x2 – 16x 

6. Example: Factoring by Using the GCF
3x3 + 2x2 – 10
3x3 =  x  x  x
Find the GCF.
2x2 = 2  x  x
10 = 2  5
There are no common factors other than 1.
3x3 + 2x2 – 10
The polynomial cannot be
factored further.

7. Example: Factoring Out a Common Binomial Factor
A. 5(x + 2) + 3x(x + 2)
(x + 2)(5 + 3x)
Factor out (x + 2).
B. –2b(b2 + 1)+ (b2 + 1)
(b2 + 1)(–2b + 1)
Factor out (b2 + 1).

8. Example: Factoring Out a Common Binomial Factor
Factor each expression.
C. 4z(z2 – 7) + 9(2z3 + 1)
There are no common factors.
4z(z2 – 7) + 9(2z3 + 1)
The expression cannot be factored.
Leave it the same way as the final answer

9. You may be able to factor a polynomial by grouping
You may be able to factor a polynomial by grouping. When a polynomial has four terms, you can make two groups and factor out the GCF from each group.

10. Example: Factoring by Grouping
6h4 – 4h3 + 12h – 8
Group terms that have a common number or variable as a factor.
(6h4 – 4h3) + (12h – 8)
2h3(3h – 2) + 4(3h – 2)
(3h – 2)(2h3 + 4)
Factor out (3h – 2). 
Check (3h – 2)(2h3 + 4) =
6h4 – 4h3 + 12h – 8

11. Lesson Quiz:
Factor each polynomial. (byb GCF)
1. 16x + 20x3
2. 4m4 – 12m2 + 8m
Factor each expression. (by grouping)
3. 7k(k – 3) + 4(k – 3)
4. 3y(2y + 3) – 5(2y + 3)