document.write( "Question 43785: in triangle ABC, a = 5, b = 9, and c = 6. Find angle A, angle B, and angle C.
\n" ); document.write( "Thanks \n" ); document.write( "

Algebra.Com's Answer #28738 by Nate(3500) $\"\"$ $\"About$

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in triangle ABC, a = 5, b = 9, and c = 6
\n" ); document.write( "Use Law of Cosines:
\n" ); document.write( " $\"a%5E2+=+b%5E2+%2B+c%5E2+-+2bc%28cos%28A%29%29\"$
\n" ); document.write( " $\"%28-a%5E2+%2B+b%5E2+%2B+c%5E2%29%2F%282bc%29+=+cos%28A%29\"$
\n" ); document.write( " $\"%28-5%5E2+%2B+9%5E2+%2B+6%5E2%29%2F%282%2A9%2A6%29+=+cos%28A%29\"$
\n" ); document.write( " $\"%28-25+%2B+81+%2B+36%29%2F%28108%29+=+cos%28A%29\"$
\n" ); document.write( " $\"%2892%29%2F%28108%29+=+cos%28A%29\"$
\n" ); document.write( " $\"cos%5E%28-1%29%2892%2F108%29+=+A\"$
\n" ); document.write( " $\"32+=+A\"$
\n" ); document.write( "Use Law of Sines:
\n" ); document.write( " $\"Sin%28A%29%2Fa+=+Sin%28B%29%2Fb\"$
\n" ); document.write( " $\"Sin%2832%29%2F5+=+Sin%28B%29%2F9\"$
\n" ); document.write( " $\"9%2ASin%2832%29%2F5+=+Sin%28B%29\"$
\n" ); document.write( " $\"sin%5E%28-1%29%289%2ASin%2832%29%2F5%29+=+B\"$
\n" ); document.write( " $\"73+=+B\"$
\n" ); document.write( "Use Law of Sum of Interior Angles: $\"180%28b+-+2%29\"$ : 180(3 - 2) : 180
\n" ); document.write( "180 - (32 + 73) = C
\n" ); document.write( "180 - 105 = C
\n" ); document.write( "75 = C \n" ); document.write( "

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