Algebra: Rational Expressions

Rational Expressions

There are lots of fancy words in the English language that describe nasty things; even the most distressing concepts don't sound so bad if they have a pretty name. Politicians know the power that certain words carry and are especially good at avoiding those and choosing other, less controversial terms. For example, who wants to go to "war," when simply being involved in a "conflict" sounds much less threatening? Most people are opposed to "tax increases," but wouldn't be automatically opposed to an "income adjustment."

In mathematics, when you mention the word "fraction," people panic. They sweat, their eyes dart about nervously, and then they sprint from the room. As a former high school math teacher, I know this from experience.

One morning, in a basic algebra class, I announced that we would be discussing fractions, and a student in the front row bolted like a frightened deer. He ran for the door, but in the process, managed to snag his pant leg on another student's desk. Caught in his innate, instinctual flight response, he couldn't think straight to turn around and free his clothing from the obstruction, and, instead, chewed his own leg off to get free.

Well, maybe that's a bit of an exaggeration. (He actually just tripped over a desk on the way to sharpen his pencil, but that's not as dramatic a story.) However, whenever I mentioned fractions, students did get wide-eyed, and most got very tense. However, if I said we'd be discussing "rational expressions," it went over much better. Even though you know that a rational number (and likewise a rational expression) is just a number that can be expressed as a fraction, for some reason the word "rational" just doesn't have the same pain and fear attached to it as the word "fraction"€”just like the word "child entertainer" doesn't inspire the fear that the phrase "scary maniacal clown" does.

Excerpted from The Complete Idiot's Guide to Algebra © 2004 by W. Michael Kelley. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

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