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Multiplication Expressions &combining Like TermsVan Siclen Community Middle SchoolGrade 6 MathClass 603/604/605March 20, 2014Table of contentsLesson OverviewYesterdays LessonYesterday we continued to practice expanding expressions and shortening expressions.Example: The expression 7ABC can be expanded and written as 7ABC.Example: The expression 5DEF can written in fewer terms as: 5DEF. We also learned about finding the product of two terms. For example, the product of 7A and 6B = 42AB. Multiply the coefficients first, and then multiply the variables.We also learned about combining like terms for the first time.Todays LessonToday we will practice combining like terms, expanding expressions, and writing expressions in the fewest terms possible.Work on the Do Now on the Next page. You have 8 minutes.HomeworkCombining like terms is a serious topic in pre-algebra mathematics. Todays homework will be graded and will count towards your marking period grade.Do NowQuestion #1Mr. E has 2 times the amount of CDs as Mr. Campbell. If Mr. E has 100 more CDs than Mr. Campbell, how many CDs do they have altogether?Question #2Find the greatest common factor of 32 and 40Find the greatest common factor of 55 and 50.Find the greatest common factor of 63 and 81Combining Like TermsEach part of an expression is called a term. For example, lets take the expression 6y + 3y. There are two coefficients. What are they?The two terms in this expression are separated by the addition sign. Therefore two terms are 6y and 3y. I can combine 6y and 3y because they are what we call like terms. They are terms that both contain the variable y. Therefore, I can combine them. 6y + 3y = 9y.5y + 5y10y - 9y10C 5C3A + 3ASolveCombining Like Terms - IIHowever, when combining like terms, we can only combine the terms that are alike. For example, in the expression 6y + 3a no terms can be combined because ys and as are not like terms. In other words, you can only combine ys with ys and as with as. Take the expression 3a + 3b + 5c. Are there any terms that can be combined? Why or why not?5y + 5y + 2a10y - 9y + a10C 5C + 3a3A + 3A 5bSolve Part IICombining Like Terms - IIIIn an expression, numbers are terms as well. For example, in the expression 6y + 3y + 10 there are 3 terms. 6y, 3y, and 10.Can you combine like terms?

How about the expression 7a + 3a + 7 6?

3y + 5y + 2a + a10y - 9y y4c 5b + 3a3A + 3A + 5b +10 + 5Combine Like terms:Combining Like Terms - IVNot all expressions are going to be written in a convenient order. For example, look at the following two expressions:Expression # 1: 3A + 4A + 5B +10Expression # 2 : 3A + 5B +4A + 10If you notice, in both expressions, the terms are the same, however the order is different (in the second expression, 4A is written in a different part of the expression). We still need to combine 3A and 4A. What sign is in front of 4A? This is the sign we use to combine the terms. Since there is an addition sign in front of the 4A, well add 3A + 4A.

3y + 5y + 2a + a10y - 9y y4c 5b + 3a3A + 3A + 5b +10 + 5Combine Like terms:Todays classworkShorten the Expressions34ab65B7ABC472JW5102DExpand the Expressions15AB12G56AB13B16ABC10DCACombine Like Terms5B + 3B + 3C -10 5A + 3A +10 5 2A3C +10A 10A + 015b + 5b 10b + 3c c10 + 5 4 +3c3c + 3a + 3b6a + 5a + 3c + 2bMath Homework March 20, 2014Combine Like terms10a + 5b 5a2) 7a + 3a 5b 2b3)13c 4a 6b4) 15+10 5B5) 10c - 15 + 3c c6) 6d 5b 2c7) 3 + 10 4b + 3a 3a8) 6p + 10a 3p + 10a 3c

Complete these questions on the back of the worksheet.