Chapter 8

Using Variables in Algebraic Expressions


Check Understanding how a variable such as x stands for a number

Check Using substitution to evaluate an algebraic expression

Check Identifying and rearranging the terms in any algebraic expression

Check Simplifying algebraic expressions

People use algebra to solve problems that are just too difficult for ordinary arithmetic. And because number-crunching is so much a part of the modern world, algebra is everywhere (even if you don’t see it): architecture, engineering, medicine, statistics, computers, business, chemistry, physics, biology, and of course, higher math. Anywhere that numbers are useful, algebra is there. That’s why virtually every college insists that you leave (or enter) with at least a passing familiarity with algebra.

In this chapter, I introduce (or reintroduce) you to algebra in a way that’s bound to make it seem a little friendlier. Then I show you how algebraic expressions are similar to and different from the arithmetic expressions that you’re used to working with. (For a refresher on arithmetic expressions, see Chapter ...

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