Three Facts Necessary to Find a Triangle
Date: 09/13/2002 at 10:50:02 From: Chris Engle Subject: Right Triangles, Advanced Pythagorean Theorem I was wondering if there were any formulas where one could solve for a right triangle given only the length of one leg and no angles except for the known 90-degree angle. For example, a right triangle with one leg equaling 15 units the right angle 0 degrees. /| /?| ? / | / |-15 units / _| /? | |-90 degree angle ------ ? I would like o know if there are any known formulas for solving for the other leg and the hypotenuse without using the 90-degree angle, i.e. without using sin, cos, or tan. Thanks in advance. Sincerely, Chris
Date: 09/13/2002 at 12:02:14 From: Doctor Peterson Subject: Re: Right Triangles, Advanced Pythagorean Theorem Hi, Chris. There is not enough information here. In general, you need three facts about a triangle in order to determine the triangle (that is, to be able to know just what triangle it is); but you know only two. For example, this will fit the known facts about your triangle just as well as the one you drew: /| / ?| ? / | / |-15 units / _| /? | |-90 degree angle ------------ ? But all the "?"s are different in this triangle. So there is no way to find their values. If you have any further questions, feel free to write back. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
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