1. Questions about 3.9 HW?  P. 167 #1-17all

2. 3.10 Add and Subtract Rational Expressions 3.9-3.10 Quiz: Friday 3.11 Quiz: April 21 Performance Exam: April 23 3.9-3.11 Test: April 28

3. Vocabulary  The least common denominator (LCD) of two or more rational expressions is the product of the factors of the rational expressions with each common factor used only once.

4. Example 1:  Find the sum or difference They have a common denominator

5. Example 2:  Find the LCD of the rational expressions. Factor each denominator and see what they have in common and then what they need to match!

6. Example 3:  Find the sum Find the LCM of 18x 2 and 9x 3 : 18x 2  9 * 2 * x * x 9x 3  9 * 1 * x * x * x LCM 

7. You Try:  Find the sum Find the LCM of 18x 2 and 9x 3 : 18x 2  4 * 3 * x * x 9x 3  4 * 4 * x * x * x * x * x LCM  4*4*3*x*x*x*x*x = 48x 5

8. Example 4:  Find the difference  Homework: START NOW! P. 173 #1-21odd