© 2007 M. Tallman

Commutative Property

© 2007 M. Tallman The order of the addends does not change the sum = addends sum = 3 + 5

© 2007 M. Tallman =5+38 8=3+5

 = j + 5  12 + p =  f f + 73 =  = 42 + s j = 3 p = 9 f = 8 s = 6 Use the Commutative Property to find the value of the variable.

© 2007 M. Tallman Commutative Property Associative Property

© 2007 M. Tallman The way the addends are grouped does not change the sum. In math, parentheses are used to group numbers. They tell us which part of the problem to solve first. = ( ) (3 + 2) + 4 = 3 + (2 + 4)

© 2007 M. Tallman 9 (3+2)+4 = =9 (3+2)+4

 (9 + 2) + 8 = w + (2 + 8) 9 + e) + 6 = 9 + (14 + 6)  y y + (67 + 5) = ( ) + 5  15 + (4 + 2) = (15 + 4) + h w = 9 e = 14 y = 21 h = 2 Use the Associative Property to find the value of the variable.

© 2007 M. Tallman Commutative Property Associative Property Identity Property

© 2007 M. Tallman The sum of any number and 0 equals the number = 11

=11+0

© 2007 M. Tallman Use the Identity Property to find the value of the variable.  = u  18 + b = 18  z z + 67 = 67 889 = 0 + s u = 3 b = 0 z = 0 s = 89

© 2007 M. Tallman

9 + 7 = 7 + 9

© 2007 M. Tallman 2 + (6 + 8) = (2 + 6) + 8

© 2007 M. Tallman = 17

© 2007 M. Tallman (10 + 4) + 5 = 10 + (4 + 5)

3 + 0 = 3

© 2007 M. Tallman =

© 2007 M. Tallman = 9 + 6

© 2007 M. Tallman 3 + (5 + 6) = (3 + 5) + 6

© 2007 M. Tallman = 345