document.write( "Question 854203: I have a triangle with two equal sides 276\". Angle between the two equal sides is 16.3636364.
\n" ); document.write( "What is the length of the other side of the triangle
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Algebra.Com's Answer #514543 by Theo(13342)\"\" \"About 
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the other 2 angles of the triangle will be equal to (180 - 16.3636364)/2.\r
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\n" ); document.write( "\n" ); document.write( "this makes each of them equal to 81.8181818.\r
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\n" ); document.write( "\n" ); document.write( "you can use the law of sines to find the third side.\r
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\n" ); document.write( "\n" ); document.write( "the law of sines says that a/sinA = b/sinB = c/sinC\r
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\n" ); document.write( "\n" ); document.write( "let A = the angle that is 16.3636364 degrees and let a = x because that's the side opposite that angle that we don't know about.\r
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\n" ); document.write( "\n" ); document.write( "let B = one of the angles that is 81.8181818 degrees and let b = 276 because that's the side opposite that angle that we do know about because it was given.\r
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\n" ); document.write( "\n" ); document.write( "the part of the law of sines formula that we are interested in is:\r
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\n" ); document.write( "\n" ); document.write( "a/sinA = b/sinB\r
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\n" ); document.write( "\n" ); document.write( "that becomes x /sin(16.3636364) = 276 / sin(81.8181818)\r
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\n" ); document.write( "\n" ); document.write( "multiply both sides of this formula by sin(16.3636364) and you get:\r
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\n" ); document.write( "\n" ); document.write( "x = 276 * sin(16.3636364) / sin(818181818) which gets you x = 78.5577909 inches.\r
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\n" ); document.write( "\n" ); document.write( "you can confirm this is true by seeing that the ratio based on the law of sines is true.\r
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\n" ); document.write( "\n" ); document.write( "78.5577909 / sin(16.3636364) is equal to 278.8381705.\r
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\n" ); document.write( "\n" ); document.write( "276 / sin(81.8181818) is equal to 278.8381705.\r
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\n" ); document.write( "\n" ); document.write( "the ratios are the same so the solution is good.\r
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\n" ); document.write( "\n" ); document.write( "you could also have solved this using the law of cosines as follows:\r
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\n" ); document.write( "\n" ); document.write( "the formula to use is c^2 = a^2 + b^2 - 2*a*b*cosC.\r
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\n" ); document.write( "\n" ); document.write( "let C be the angle that you know about.
\n" ); document.write( "c is the side opposite this angle.
\n" ); document.write( "a and b are each 276 inches.
\n" ); document.write( "these are the sides that are opposite the other 2 angles that we don't know about and don't need to know about if we are using the law of cosines formula.\r
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\n" ); document.write( "\n" ); document.write( "the law of cosines formula becomes:
\n" ); document.write( "c^2 = 276^2 + 276^2 - 2*276*276*cos(16.3636364).
\n" ); document.write( "solve this to get c^2 = 6171.326511
\n" ); document.write( "take the square root of both sides to get:
\n" ); document.write( "x = 78.5577909\r
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\n" ); document.write( "\n" ); document.write( "you get the same answer either way.
\n" ); document.write( "that's good.\r
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