1. HW answers.

2. Warm-up Add or Subtract without using a calculator

3. Adding and Subtracting Rational Expressions Objectives: To find the least common denominator of two or more algebraic expressions. To add and subtract rational expressions.

4. Find the LCD for each pair of denominators

5. BIG IDEA!!! You can only add/subtract fractions with the same denominator!

6. Procedure: If the fractions have the same denominator… 1. Add/Subtract the numerators. WATCH OUT! Minus signs distribute. 2. Keep the same denominator. 3. Reduce answer if possible.

7. Adding and Subtracting Rational Expressions Example #1a Example #1b

8. If the fractions don’t have the same denominators… You MUST make them have the same denominator before you can add or subtract them.

9. Building a Least Common Denominator (LCD) BIG IDEA!!! An LCD will show the factors of both denominators!

10. PROCEDURE: 1. Factor each denominator completely. 2. Multiply the top and bottom of each fraction by the missing factors. 3. Rewrite as one large fraction. This will help you avoid sign errors. 4. Multiply out the numerator and then combine like terms. 5. Factor and reduce if possible.

11. Adding and Subtracting Rational Expressions Example #2a Example #2b

12. Adding and Subtracting Rational Expressions Example #3a Example #3b

13. Adding and Subtracting Rational Expressions Example # 4a

14. Adding and Subtracting Rational Expressions Example # 4a

15. TOTD 1. Write as the difference of two fractions. 2. Does Why or why not?

16. Class work worksheet