document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=557916>Question 557916</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do you find the number of diagonals with just knowing the number of sides? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #362827 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=362827\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the number of sides is the same as the number of corners (vertices)\r<BR>\n" );
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document.write( "diagonals are lines from corner-to-corner, that aren't sides\r<BR>\n" );
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document.write( "if there are N corners; you can draw lines from any corner, to N-1 other corners\r<BR>\n" );
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document.write( "but, the line from A to B is the same as the line from B to A<BR>\n" );
document.write( "___ so the number of lines is {[N(N - 1)] / 2}\r<BR>\n" );
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document.write( "N of the lines are sides, so the number of diagonals is ___ {[N(N - 1)] / 2} - N ___ or ___ {[N(N - 3)] / 2} </SPAN>\n" );
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