document.write( "Question 1158259: Determine the number of diagonals in a decagon \n" ); document.write( "
Algebra.Com's Answer #781158 by ikleyn(52781)\"\" \"About 
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document.write( "For any convex polygon with \"n\" vertices / (sides), the number of its diagonals is \"%28n%2A%28n-3%29%29%2F2\".\r\n" );
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document.write( "For decagon (n= 10) the number of diagonals is  \"%2810%2A%2810-3%29%29%2F2\" = \"%2810%2A7%29%2F2\" = 5*7 = 35.    ANSWER\r\n" );
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