1. 5-Minute Check on Chapter 2 Transparency 3-1 Click the mouse button or press the Space Bar to display the answers. 1.Evaluate 42 - |x - 7| if x = -3 2.Find 4.1  (-0.5) Simplify each expression 3. 8(-2c + 5) + 9c 4. (36d – 18) / (-9) 5.A bag of lollipops has 10 red, 15 green, and 15 yellow lollipops. If one is chosen at random, what is the probability that it is not green? 6. Which of the following is a true statement Standardized Test Practice: ACBD 8/4 < 4/8-4/8 < -8/4-4/8 > -8/4-4/8 > 4/8

2. Lesson 9-5 Factoring Differences of Squares

3. Transparency 5 Click the mouse button or press the Space Bar to display the answers.

4. Transparency 5a

5. Objectives Factor binomials that are the difference of squares Solve equations involving the difference of squares

6. Vocabulary NA –

7. Difference of Squares Symbols: a 2 – b 2 = (a + b) (a – b) or (a – b) (a + b) Examples: –x 2 – 9 = (x – 3) (x + 3) or (x + 3) (x – 3) –b 2 – 25 = (b – 5) (b + 5) or (b + 5) (b – 5)

8. Example 1 A. Factor. Write in form Answer: Factor the difference of squares. B. Factor. Answer: Factor the difference of squares. and

9. Example 2 Factor The GCF ofand 27b is 3b. and Answer: Factor the difference of squares.

10. Example 3 Factor The GCF of and 2500 is 4. and Factor the difference of squares. and Factor the difference of squares. Answer:

11. Example 4 is the common factor. Factor the difference of squares, into. Answer: Factor Original Polynomial Factor out the GCF. Group terms with common factors. Factor each grouping.

12. Example 5a A. Solve by factoring. Original equation. and Factor the difference of squares. or Zero Product Property Solve each equation. Answer: The solution set is

13. Example 5b Solveby factoring. Original equation Subtract 3y from each side. The GCF of and 3y is 3y. and Answer: The solution set is Applying the Zero Product Property, set each factor equal to zero and solve the resulting three equations. or

14. Summary & Homework Summary: –Difference of Squares: a 2 – b 2 = (a + b)(a - b) or (a – b)(a + b) –Sometimes it may be necessary to use more than one factoring technique or to apply a factoring more than once Homework: –Pg. 505 16-30 even, 34,36