Date: 6/28/96 at 14:58:57 From: Anonymous Subject: Factoring Rules Dear Dr. Math. I asked you a factoring question and your explanation and procedure to finding the answer was so clear that I've been wondering if there is a clear set of factoring rules or procedures that would help me with these difficult factoring exercises. I'll be going into 9th grade next September. Thank you. Jackie
Date: 6/28/96 at 17:44:11 From: Doctor Gary Subject: Re: Factoring Rules Factoring will always be more art than skill (although there are algorithms which will permit you to factor quadratic or cubic expressions, the former being much easier than the latter). The best way to improve your skill at factoring is to do some multiplying. For example, when you multiply (x+2) by (x-3), you'll notice that the product has a term of x^2, a term of -6 and a third, composite, term of (2-3)x. More generally, whenever, you multiply (x+m) by (x+n), the product will have a term of x^2, a term of mn and a composite term of (m+n)x. When the time comes that you have to factor something like: x^2 -3x -10, you'll know to be thinking in terms of some "m" and "n" such that mn is equal to -10 and (m+n) is equal to -3. Good luck, and happy factoring. -Doctor Gary, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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