document.write( "Question 698758: A triangle has sides of length 5cm, 6cm, and 9cm.
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\n" ); document.write( "i dont know what equation to use \n" ); document.write( "
Algebra.Com's Answer #431016 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "This one for the case of SSS (all three sides known):\r\n" );
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document.write( "             (ONE SIDE OF ANGLE)²+(OTHER SIDE OF ANGLE)²-(OPPOSITE SIDE OF ANGLE)² \r\n" );
document.write( "cos(ANGLE) = ---------------------------------------------------------------------\r\n" );
document.write( "                      2×(ONE SIDE OF ANGLE)×(OTHER SIDE OF ANGLE)\r\n" );
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document.write( "cos(x) = \"%285%5E2%2B9%5E2-6%5E2%29%2F%282%2A5%2A6%29\"\r\n" );
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document.write( "cos(x) = \"%2825%2B81-36%29%2F60\"\r\n" );
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document.write( "Work that out, then use the inverse cosine\r\n" );
document.write( "feature on your calculator to get\r\n" );
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document.write( "x = 38.9424127 or 38°56'32.789\"\r\n" );
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document.write( "Edwin
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