document.write( "Question 1008804: PLease help me Find the measure of angle A in Triangle ABC to the nearest degree if A= 4, B= 13, and C= 45 degrees?
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Algebra.Com's Answer #627644 by Fombitz(32388) $\"\"$ $\"About$

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I assume that $\"a=4\"$ and $\"b=13\"$ are measures of the sides.
\n" ); document.write( "Use the law of cosines to find the unknown side, $\"c\"$ .
\n" ); document.write( " $\"c%5E2=a%5E2%2Bb%5E2-2ab%2Acos%28C%29\"$
\n" ); document.write( " $\"c%5E2=4%5E2%2B13%5E2-2%284%29%2813%29%2Acos%2845%29\"$
\n" ); document.write( " $\"c%5E2=16%2B169-104%2A%28sqrt%282%29%2F2%29\"$
\n" ); document.write( " $\"c%5E2=111.461\"$
\n" ); document.write( " $\"c=10.56\"$
\n" ); document.write( "Then use the law of sines,
\n" ); document.write( " $\"a%2Fsin%28A%29=c%2Fsin%28C%29\"$
\n" ); document.write( " $\"4%2Fsin%28A%29=10.56%2Fsin%2845%29\"$
\n" ); document.write( " $\"sin%28A%29=%284%2Asin%2845%29%29%2F10.56\"$
\n" ); document.write( " $\"sin%28A%29=0.2679\"$
\n" ); document.write( " $\"A=15.5\"$
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