Distributive PropertyDate: 10/29/97 at 23:49:03 From: Nicole Subject: Distributive Property I am in a ninth grade algebra class, although I am only in the 8th grade. I am really stuck on this Distributive Property thing. I don't understand it at all. Can you help me? Date: 11/04/97 at 15:10:29 From: Doctor Pipe Subject: Re: Distributive Property The Distributive Property is one of the basic properties of the real numbers. You are wise to keep trying to understand it. Try this. To distribute something means to hand it out. If you distribute a test paper to your class, you give a test to each person in the class. The Distributive Property says that if a, b, and c are real numbers, then a x (b + c) = (a x b) + (a x c) Both b and c share a on the left side of the equation; on the right side of the equation the a has been distributed to b and c. Let's take a specific case: 5 x (2 + 3). The distributive property says that this is the same as (5 x 2) + (5 x 3). When we write: 5 x (2 + 3) = (5 x 2) + (5 x 3) we say that we have distributed the five to the two and the three. Both sides of the equation are equal so they will work to the same answer: 5 x (2 + 3) (5 x 2) + (5 x 3) = 5 x 5 = 10 + 15 = 25 = 25 Using our example, the Distributive Property says that five times the sum of two plus three is equal to the product of five times two plus the product of five times three. Using coins to show this, take twenty-five pennies. First, make five stacks of two pennies and five stacks of three pennies. This represents the righthand side of the equation above: five times two plus five times three (or written mathematically: (5 x 2) + (5 x 3)). Now pair each stack of two pennies with a stack of three pennies. This represents the left side of the example above: five groups, two plus three in each group (or written mathematically: 5 x (2 + 3)). What a strange world it would be if you could take twenty-five pennies and have more or less than 25 based on how you grouped them! Keep trying - you WILL understand this - and more! You might even have fun .... -Doctor Pipe, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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