The Why of Algebra
Date: 11/13/98 at 08:33:58 From: brittney smith Subject: Algebra I don't get the point of algebra. What is algebra for, when we have multiplication and division?
Date: 11/13/98 at 11:53:27 From: Doctor Rick Subject: Re: Algebra Hi, Brittney. Don't let your loyalty to your old friends multiplication and division keep you from making friends with algebra. Algebra doesn't replace them at all. What algebra does is to help you decide when to multiply and divide. It is a problem-solving tool. The basic trick that makes algebra work is this. Say there's some quantity, like a weight or an amount of money, that you don't know. The fact is, even though you don't know the exact number, you know a great deal about it just because you know it's a number. So you give it a name (a variable) and you treat it just as if it were a number that you know. By applying certain rules that work for all numbers, you can figure out what the number must be. Algebra is a toolbox full of tools that help you take a problem apart and put it back together. Multiplication might be the screwdriver, but your algebra toolbox also has clamps that hold the pieces so the screw will go in the right place. Algebra is also a language that lets you talk about a problem, and think about it. When I try to help a pre-algebra student solve a word problem, it's hard, because I don't know what words to use to explain how I thought about the problem. But if I can use algebra, I just have to define some variables and write an equation, and explain which rules to use to change the equation until you get the answer. Those are just a few thoughts on what algebra is good for. Don't sell it short. Algebra will be a good friend to have some day when you're wondering, "Should I add first, or multiply?" - Doctor Rick, The Math Forum http://mathforum.org/dr.math/
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