Algebra: Factoring Polynomials
I remember the first day I tried to drive in reverse. I didn't think it would be significantly harder (after all, walking backwards is no harder than walking forwards, so why should driving be any different?), but boy, was I wrong. Everything feels different when you're backing up. No matter which way you turn the wheel, the car seems to go in the opposite direction you intend. I still get a little antsy in reverse sometimes; it's a whole new ballgame.
Now that you are used to multiplying polynomials (in my metaphor, the equivalent of driving), now it's time to throw the whole process in reverse and learn factoring.
Why is factoring the reverse of multiplication, you ask? It's because factoring is the process of taking what was once a product and breaking it into the original pieces (called factors) that multiply together to get that product.
In Introducing Polynomials, you learned to calculate (x - 3)(x + 5) = x2 + 2x - 15. In this section, you'll start with x2 + 2x - 15 and wind up with (x - 3)(x + 5). At first, things will feel a little strange, like driving in reverse originally does, but soon you'll master it as well.
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.