Meanings of PropertiesDate: 07/23/97 at 17:31:13 From: Colleen Subject: Wording I have no idea what these words mean, and I need help. Can you help me out? It's appreciated. What do Associative Property, Commutative Property, and Distributive Property mean? Date: 07/23/97 at 17:53:08 From: Doctor Wilkinson Subject: Re: wording The associative property and the commutative property apply to the operations of addition and multiplication; the distributive property applies to the two operations working together. The associative property says that when you add or multiply three or more numbers, it doesn't matter how you group them: that is, we have the formulas (a + b) + c = a + (b + c) and (a x b) x c = a x (b x c) For example (4 + 6) + 5 = 10 + 5 = 15, which is the same thing you get if you add 4 + (6 + 5) = 4 + 11 = 15 The commutative property says it doesn't matter which order you add or multiply two numbers in: the formulas are a + b = b + a and a x b = b x a For example, 4 x 7 = 28 = 7 x 4 The distributive property tells you what happens if you add two numbers and multiply the sum by another number. This formula is a x (b + c) = a x b + a x c For example, 3 x (4 + 5) = 3 x 9 = 27 which is the same thing you get if you multiply 3 by 4 and 3 by 5 and add the two answers together: 3 x 4 + 3 x 5 = 12 + 15 = 27 You use these properties without thinking much about them when you do arithmetic, but when you do algebra you have to be aware of them. -Doctor Wilkinson, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/