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Warm up #2 Ch 1: SIMPLIFY if possible. Warm-Up #2 Ch 1: SIMPLIFY if possible. 1.2 Commutative, Identity, and Associative Properties. We will write equivalent expression using the properties. Vocabulary:. Equivalent Expression:
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1.2 Commutative, Identity, and Associative Properties We will write equivalent expression using the properties
Vocabulary: • Equivalent Expression: Expressions that have equal values for the same replacement values of their variables
Commutative Properties Multiplication • 3 • 8 = 8 • 3 • We can change the order when multiplying without affecting the product. Addition • 7 + 3 = 3 + 7 • We can change the order when adding without affecting the sum.
Commutative Properties Subtraction • 7 - 3 = 3 – 7 ?? • Commutative Property does NOT apply to subtraction. Division • 3 ÷ 8 = 8 ÷ 3 ?? Commutative Property does NOT apply to division.
To commute means to move • The news talks about the daily commute on the freeway. • Think about how the cars move this will help you to remember commutative property is when the numbers move!
Commutative Property + = Addition Multiplication +
Write an equivalent expression using the commutative prop • 7 + 11 • 3 +x • 5y
Why is the Commutative Property helpful? It can help you to do more simple calculations
For Example: 200 264
Mental Math 8 72
Identity Properties Addition • 7 + 0 = 7 • When zero is added to any number, the sum is the same number. Multiplication • 9 • 1 = 9 • When any number is multiplied by 1, the product is the same number.
Identity is who you are • Same with numbers. We want to be able to do an operation (such as +0 or mult by 1) and get the same thing back, its identity
Equivalent Expressions (Using the Identity Property of Multiplication) Do you reduce this???
Answer is: NO!!!! • Usually we reduce everything! • We reduce when the directions say to: • Simplify • Evaluate • Solve • Calculate (add, sub, mult, divide) • When the directions say to write an equivalent expression we do not reduce
The Associative Property (Parenthesis) around different pairs of numbers (a + b) + c = a + (b + c) (5 + 2) + 3 = 5 + (2 + 3)
The Associative Property (Parenthesis) around different pairs of numbers (a • b) • c = a • (b • c) (2 • 3) • 5 = 2 • (3 • 5)
Associative: To associate ( ) + + + ( ) +