document.write( "Question 1001510: the side of a triangle measure 16 centimeters, 13 centimeters, and 11 centimeters, what are the measures of the angles of the triangle
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Algebra.Com's Answer #618769 by KMST(5328)\"\" \"About 
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In a right triangle the longest side is the hypotenuse,
\n" ); document.write( "and if \"a\"= length of the hypotenuse, with \"b\" and \"c\" being the other sides lengths,
\n" ); document.write( "\"a%5E2=b%5E2%2Bc%5E2\" (the Pythagorean relationship).
\n" ); document.write( "In any triangle ABC,
\n" ); document.write( "\"a%5E2=b%5E2%2Bc%5E2-2bc%2Acos%28A%29\" (the law of cosines).
\n" ); document.write( "(We can also write it as \"b%5E2=a%5E2%2Bc%5E2-2ac%2Acos%28B%29\" or \"c%5E2=a%5E2%2Bb%5E2-2ab%2Acos%28C%29\" ).
\n" ); document.write( "So if \"a=16\"= length of side opposite angle A
\n" ); document.write( "\"16%5E2=13%5E3%2B11%5E2-2%2A13%2A11%2Acos%28A%29\"
\n" ); document.write( "\"256=169%2B121-286%2Acos%28A%29\"
\n" ); document.write( "\"286%2Acos%28A%29=169%2B121-256\"
\n" ); document.write( "\"286%2Acos%28A%29=34\"
\n" ); document.write( "\"cos%28A%29=34%2F286\"--->\"A=about1.4516\" or \"A=about83.17%5Eo\" (rounded)
\n" ); document.write( "NOTE:
\n" ); document.write( "We can also write the law of cosines as
\n" ); document.write( "\"b%5E2=a%5E2%2Bc%5E2-2ac%2Acos%28B%29\" or \"c%5E2=a%5E2%2Bb%5E2-2ab%2Acos%28C%29\" .\r
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\n" ); document.write( "\n" ); document.write( "To find the measure of another angle,
\n" ); document.write( "we can apply the law of cosines again,
\n" ); document.write( "or we can use the law of sines.
\n" ); document.write( "After that, we find the remaining angle by using the fact that the measures of all 3 angles add up to \"pi\" or \"180%5Eo\" .\r
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\n" ); document.write( "\n" ); document.write( "USING LAW OF COSINES AGAIN:
\n" ); document.write( "let \"B\" be the angle opposite the side with length \"b=13\"cm.
\n" ); document.write( "\"13%5E2=16%5E2%2B11%5E2-2%2A16%2A11%2Acos%28B%29\"
\n" ); document.write( "\"169=256%2B121-352%2Acos%28B%29\"
\n" ); document.write( "\"352%2Acos%28B%29=256%2B121-169\"
\n" ); document.write( "\"352%2Acos%28B%29=208\"
\n" ); document.write( "\"cos%28B%29=208%2F352\"--->\"B=about0.9386\" or \"B=about53.78%5Eo\" (rounded).\r
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\n" ); document.write( "\n" ); document.write( "USING LAW OF SINES FOR A CHANGE:
\n" ); document.write( "If you have the measures of one side and the opposite angle of a triangle,
\n" ); document.write( "you can apply the law of sines, which states
\n" ); document.write( "\"sin%28B%29%2Fb=sin%28A%29%2Fa=sin%28C%29%2Fc\"
\n" ); document.write( "So, with \"b=13\"cm,
\n" ); document.write( "\"sin%28B%29%2F13=sin%28A%29%2F16\"--->\"sin%28B%29=13sin%28A%29%2F16\"
\n" ); document.write( "\"sin%28A%29=about0.9929\" (rounded), so
\n" ); document.write( "\"sin%28B%29=about13%2A0.9929%2F16\"--->\"B=about0.9386\" or \"B=about53.78%5Eo\" (rounded).\r
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\n" ); document.write( "\n" ); document.write( "Once we have \"system%28A=about1.4516%2CB=about0.9386%29\" or \"system%28A=about83.17%5Eo%2CB=about53.78%5Eo%29\"
\n" ); document.write( "We can find
\n" ); document.write( "\"C=pi-about1.4516-about0.9386=about0.7514\" or
\n" ); document.write( "\"C=180%5Eo-83.17%5Eo-about53.78%5Eo=about43.05%5Eo\" .
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