document.write( "Question 436544: Hi am slightly stuck on this question in geometry\r
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\n" ); document.write( "\n" ); document.write( "abc=4∆R where ∆ is the area of the triangle and R is the radius of the circumcircle of the triangle
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Algebra.Com's Answer #302044 by richard1234(7193)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Assume a,b,c are the side lengths opposite vertices A,B,C respectively. From the extended law of sines,\r
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\n" ); document.write( "\n" ); document.write( "\"a%2Fsin%28A%29+=+b%2Fsin%28B%29+=+c%2Fsin%28C%29+=+2R\"; this implies \"sin%28A%29+=+a%2F2R\".\r
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\n" ); document.write( "\n" ); document.write( "Note that the area of the triangle is equal to \"DELTA+=+bc%2Asin%28A%29%2F2\". We can substitute \"sin%28A%29\" to obtain\r
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\n" ); document.write( "\n" ); document.write( "\"DELTA+=+bc%28a%2F2R%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"DELTA+=+abc%2F4R\"\r
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\n" ); document.write( "\n" ); document.write( "\"abc+=+4R%2ADELTA\" as desired.
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