Grade 6 Lesson 1.3: Properties of Addition and Multiplication Essential Question: How can you use properties to show that two expressions are equivalent? Lesson Objective: Use the Commutative and Associative Properties, and two other properties, to show that expressions are equivalent. Vocabulary: equivalent expressions Previous Learning: Students need to be familiar with basic computation facts. Applying mental math strategies will be helpful. Pacing: 45 minutes CC State Standards CC Mathematical Practice Focus 6.EE.3, 6.EE.6 MP3a.1 1. INTRODUCTION (5 minutes) Warm Up Have students answer Start Thinking! and/or Warm Up questions. Review the answers as a class. Review previously assigned homework, if necessary. Other Resources Start Thinking! and Warm Up Homework Check Answer Presentation Tool Laurie’s Lesson Notes Discuss from Laurie’s Notes in Teaching Edition Discuss what the word equivalent means using real-life examples. Then discuss equivalent fractions and equivalent measures. Define equivalent expressions and relate this to the equivalent things previously discussed. 2. KEY IDEAS (5 minutes) Other Resources Commutative and Associative Properties Dynamic Classroom Laurie’s Lesson Notes These Key Ideas introduce the Commutative and Associative Properties of Addition and Multiplication that students will use to write equivalent expressions. Write the Commutative and Associative Properties. Give an example. Copyright © Big Ideas Learning, LLC All rights reserved. Big Ideas Math Green Lesson Plan 3. EXAMPLE 1 (10 minutes) Other Resources Focus on MP3a.1 Dynamic Classroom Laurie’s Lesson Notes Extra Example Allow students to use the results from the activities to simplify algebraic expressions. Don’t let the students become confused because of the use of a variable. The process is the same when using whole numbers, fractions, decimals or variables. Using Properties to Simplify Expressions This example illustrates how the Commutative and Associative Properties are used to write equivalent expressions by simplifying expressions such as 7 (12 x) , (6.1 x) 8.4 , or 5(11 y ) . Work through the written examples in parts (a)–(c) as a class. Have students simplify the expression and explain each step. Have students work independently to answer the On Your Own questions. Then have neighbors check each other’s work. Review the answers together, with students presenting their work to the class. 4. KEY IDEAS (5 minutes) Other Resources Addition Property of Zero/Multiplication Properties of Zero and One Dynamic Classroom Laurie’s Lesson Notes These Key Ideas introduce the Addition Property of Zero and the Multiplication Properties of Zero and One that students will use to write equivalent expressions. Write the Addition Property of Zero and the Multiplication Properties of Zero and One. Give an example. 5. EXAMPLE 2 (5 minutes) Other Resources Using Properties to Simplify Expressions Dynamic Classroom Laurie’s Lesson Notes Extra Example This example illustrates how the Addition Property of Zero and the Multiplication Properties of Zero and One are used to write equivalent expressions by simplifying expressions, such as 9 0 p or 4.5 r 1 . Work through the examples in parts (a) and (b). Have students simplify the expression and explain each step. 6. EXAMPLE 3 (10 minutes) Other Resources Real-Life Application Dynamic Classroom Laurie’s Lesson Notes Extra Example This example illustrates how to write an expression and then simplify it using the properties introduced in this lesson, such as simplifying an expression of the total amount paid by a basketball team sponsor for the league fee, T-shirts, and trophies. Solve Example 3 with the class using Laurie’s Lesson Notes. Have students use Think-Pair-Share to answer the On Your Own questions. Review the answers together, with students presenting their work to the class. Copyright © Big Ideas Learning, LLC All rights reserved. Big Ideas Math Green Lesson Plan 7. ASSESS (5 minutes) Closure (as time allows) As a class, answer the closure question from the Teaching Edition that has students give examples of the Commutative and Associative Properties using variables and numbers. This is a good way of summarizing the Commutative and Associative Properties. Other Resources Taking Math Deeper Mini-Assessment Extra Practice (A and B) Big Ideas Test Generator Focus on MP3a.1 Allow students to practice the properties they have just learned. Have each student select an exercise from 1223 and ask them to rewrite the problem using the Which One Doesn’t Belong format from Exercise 4. Have them trade the results with a partner to see if they can correctly write the expression and identify the incorrect phrase. Homework Assignment 1–4, 11–23 odd, 24–32 even Suggestions for leveling BASIC: Homework Assignment 1–4, 5–23 odd, 24, 25, 27 ADVANCED: Homework Assignment 1–4, 11, 12–22 even, 28–34 even Copyright © Big Ideas Learning, LLC All rights reserved. Other Resources Puzzle Time Record and Practice Journal Lesson Tutorials Skills Review Handbook Enrichment and Extension Differentiating the Lesson Big Ideas Math Green Lesson Plan