1. 5-2 Adding and Subtracting with Unlike Denominators Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day Lesson Quizzes Lesson Quizzes

2. 5-2 Adding and Subtracting with Unlike Denominators Do Now Add. Write each answer in simplest form. 1. +2. + 3. + 4. + 1 7 __ 1 7 8 15 __ 3 15 __ 7 9 2 9 11 20 __ 4 20 __ 2 7 11 15 __ 1 3 4

3. 5-2 Adding and Subtracting with Unlike Denominators SWBAT add and subtract fractions with unlike denominators by finding the LCD. Objective:

4. 5-2 Adding and Subtracting with Unlike Denominators Vocabulary least common denominator (LCD) ‏

5. 5-2 Adding and Subtracting with Unlike Denominators The Arctic Ocean covers of Earth’s surface. The Indian Ocean covers of Earth’s surface. To find the fraction of Earth’s surface that is covered by both oceans, you can add and, which are unlike fractions. 1 8 __ 1 8 1 6 1 6

6. 5-2 Adding and Subtracting with Unlike Denominators We already know... to add or subtract unlike fractions, first rewrite them as equivalent fractions with a common denominator. You can use any common denominator or the least common denominator to add and subtract unlike fractions. The least common denominator (LCD) is the least common multiple of the denominators.

7. 5-2 Adding and Subtracting with Unlike Denominators Ex. 1 : Adding and Subtracting Unlike Fractions Add or subtract. Write each answer in simplest form. 7 10 __ 3 8 – Use the LCD Find the LCD (LCM of the denominators) Make equivalent fractions Subtract Simplify Vertically align the fractions

8. 5-2 Adding and Subtracting with Unlike Denominators Communicator Activity Find the least common denominator of the following fractions. Write equivalent fractions.

9. 5-2 Adding and Subtracting with Unlike Denominators Communicator Activity Find the least common denominator of the following fractions. Write equivalent fractions.

10. 5-2 Adding and Subtracting with Unlike Denominators Communicator Activity Find the least common denominator of the following fractions. Write equivalent fractions.

11. 5-2 Adding and Subtracting with Unlike Denominators Let’s do this one together... Add or subtract. Write each answer in simplest form. 5 16 __ 1 8 + Use the LCD Find the LCD (LCM of the denominators) Make equivalent fractions Subtract Simplify Align the fractions vertically

12. 5-2 Adding and Subtracting with Unlike Denominators Do Now Add or subtract using the LCD. Write each answer in simplest form. 1.) – 2.) – 11 12 __ 3 8 8 10 __ 2 6

13. 5-2 Adding and Subtracting with Unlike Denominators Homework: Pg. 200, #’s 16-23 Find each sum or difference. Write each answer in simplest form.

14. 5-2 Adding and Subtracting with Unlike Denominators Communicator Activity Add or subtract the following fractions using the LCD. Write your answer in simplest form.

15. 5-2 Adding and Subtracting with Unlike Denominators Do Now – In Your Notes! Find each sum or difference.

16. 5-2 Adding and Subtracting with Unlike Denominators Standard Lesson Quiz Lesson Quizzes Lesson Quiz for Student Response Systems

17. 5-2 Adding and Subtracting with Unlike Denominators Lesson Quiz Add or subtract. Write each answer in simplest form. 1. +2. – 3. – 4. + 5. Bonnie is making oatmeal bars and the recipes calls for cup of brown sugar. If she has cup of brown sugar, how much more does she need? 3 8 __ 1 6 1 2 1 8 5 12 __ 1 6 1 6 1 8 3 4 1 3 13 24 __ 3 8 1 4 7 24 __ 5 12 __ cup

18. 5-2 Adding and Subtracting with Unlike Denominators 1. Add and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems

19. 5-2 Adding and Subtracting with Unlike Denominators 2. Subtract and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems

20. 5-2 Adding and Subtracting with Unlike Denominators 3. Subtract and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems

21. 5-2 Adding and Subtracting with Unlike Denominators 4. Add and identify the answer in simplest form. A. C. B. D. Lesson Quiz for Student Response Systems

22. 5-2 Adding and Subtracting with Unlike Denominators 5. Donna is making tomato soup and the recipe calls for kg of tomato. If she has kg of tomatoes, how much more does she need? A. C. B. D. Lesson Quiz for Student Response Systems