document.write( "Question 626627: how many diagonals are there in 23 sides?
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\n" ); document.write( "how many sides are there in 1377 diagonals?\r
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Algebra.Com's Answer #394366 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi,
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document.write( "Note:  \"D+=+n%28n-3%29%2F2\"
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document.write( "how many diagonals are there in 80 sides? \"D+=+80%2880-3%29%2F2\"
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document.write( "how many sides are there in 152 diagonals?
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document.write( " \"152+=+n%28n-3%29%2F2\"
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document.write( "   304 = n^2 - 3n
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document.write( "     n^2 - 3n - 304 = 0
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document.write( "\"n+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
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document.write( "\"n+=+%283+%2B-+sqrt%28+1225%29%29%2F%282%29+\"
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document.write( " \"n+=+%283+%2B-+35%29%2F%282%29+\"
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document.write( "    n = 19   (tossing out negative solution for n)\r
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