document.write( "Question 920288: If nC12 = nC8, find out what n is. \n" ); document.write( "
Algebra.Com's Answer #558277 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Use the fact that\r\n" );
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document.write( " nCr = nC(n-r)\r\n" );
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document.write( "nC12 = nC8\r\n" );
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document.write( "Comparing those, you get the two equations:\r\n" );
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document.write( "r=12\r\n" );
document.write( "n-r=8\r\n" );
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document.write( "Substitute 12 for r in the second one\r\n" );
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document.write( "n-12=8\r\n" );
document.write( "   n=20\r\n" );
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document.write( "Checking with a TI-84 calculator:\r\n" );
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document.write( "nC12 = nC8\r\n" );
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document.write( "20C12 = 20C8\r\n" );
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document.write( "125970 = 125970\r\n" );
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document.write( "Edwin
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