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can I determine the length of sides of a triangle?

Posted 11 years ago
Knowing the angles (1, 89, 90) and one side length, can I identify the remaining 2 side lengths?   How would I input this to Wolfram Alpha?
POSTED BY: George Rowlett
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POSTED BY: George Rowlett
Here are a couple ways of inputing this question into WolframAlpha.

First, you can use something like "1-89-90 triangle side lengths" [link] to get the relative sizes of the edges, from which it should be easy to get the others.

Second, you can use the "law of sines" [link] which relates edges lengths to angle. For this, WolframAlpha allows you to enter an edge length and two angles, and get the second edge length back. For your particular triangle, the 89 and 90 degree angles are similar, and I found it useful to use an edge length with a lot of digits (eg. 1.0000000000) to get enough digits back to be useful.
POSTED BY: Brett Champion
Is this a "dumb" question?  Can it not be calculated?  Memory of math classes in my youth make me believe that knowing all the angles and the length of one side that is not the hypotenuse would enable me to calculate the other side lengths.  Am i missing something obvious?
POSTED BY: George Rowlett
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