document.write( "Question 647498: The question I am doing now says \"Find the measure of the unknown side\" and it shows a picture of a triangle, it says side a is 13mm, side c is 5mm and you're trying to find side b. I know how to do pythagorean therom when you need to find side c, but how do you do it when you need to find side b? \n" ); document.write( "
Algebra.Com's Answer #406239 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You know this version of the Pythagorean theorem, the one with the + sign.\r\n" );
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document.write( "c² = a² + b²\r\n" );
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document.write( "But there are two other equivalent versions of it, and they have minus signs:\r\n" );
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document.write( "a² = c² - b²\r\n" );
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document.write( "and also\r\n" );
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document.write( "b² = c² - a²\r\n" );
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document.write( "So when you are finding c you use a plus + and if you're finding a or b,\r\n" );
document.write( "you use a minus - .\r\n" );
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document.write( "Edwin
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