Geometry: Opening Doors with Similar Triangles

Opening Doors with Similar Triangles

You just spent a whole section talking about similar triangles, but you didn't actually do much with them. Oh sure, I showed you how to use theorems to prove that two triangles were similar, and you were able to measure the length of a lake using similar triangles, but there have to be more applications than that.

One of the most useful things about similar triangles is CSSTAP (corresponding sides of similar triangles are proportional). After you show that two triangles are similar, you can develop proportionalities that will help you establish relationships between the sides of the similar triangles.

In addition to using the properties of similar triangles to measure lake dimensions, you can prove the Pythagorean Theorem and show that two lines are parallel. And that's just the beginning.

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Excerpted from The Complete Idiot's Guide to Geometry © 2004 by Denise Szecsei, Ph.D.. 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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