1. 5.5 Factoring Special Patterns 11/20/2013

2. Perfect Squares 11 1 42 2 93 3 164 4 255 5 366 6 49 7 7 648 8 819 9 100 10 121 11 144 12 169 13

3. Square Root of a Number (it’s like finding the side of the perfect square) 100 = 10 81 = 9 = 8 64 = 7 49 = 6 36 25 = 5 16 = 4 = 3 9 = 2 4 = 1 1

4. Review Find the product 1.(x + 2) (x – 2) Answer: x 2 – 4 2. (x + 5) (x – 5) Answer: x 2 – 25 3. (2x – 3) (2x + 3) Answer: 4x 2 – 9 What’s the pattern???

5. Difference of Two Squares Pattern (a + b) (a – b) = a 2 – b 2 In reverse, a 2 – b 2 factors to (a + b) (a – b) Examples: 1. x 2 – 4 = (x + 2) (x – 2) 2. x 2 – 144 =(x + 12) (x – 12) 3. 4x 2 – 25 = (2x + 5) (2x – 5)

6. If you can’t remember that you can still use the big X method. Ex. x 2 – 4 -4 0 Think of 2 numbers that Multiply to -4 and Add to 0 2 x -2 = -4 2 + -2 = 0 2 -2 Answer: (x + 2) (x - 2) Ex. x 2 + 0x – 4

7. Ex. x 2 – 144 -144 0 Think of 2 numbers that Multiply to -144 and Add to 0 12 x -12 = -144 12 + -12 = 0 12 -12 Answer: (x + 12) (x - 12) x 2 + 0x – 144

8. 4(-25) = -100 0 Think of 2 numbers that Multiply to -100 and Add to 0 -10 x 10 = -100 -10 + 10 = 0 -10 10 Answer: (2x - 5) (2x + 5) Factor: 4x 2 - 25 44 Simplify like a fraction. ÷ by 2 -5 2 5 2 Simplify like a fraction. ÷ by 2 4x 2 + 0x - 25

9. Homework: WS 5.3-5.5 Quiz 5.3-5.5 Friday!!!