document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1180622>Question 1180622</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A decagonal trapezohedron has 20 faces, each of<BR>\n" );
document.write( "which is a kite. How many vertices are there on a<BR>\n" );
document.write( "decagonal trapezohedron? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #810362 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=810362\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "One tutor apparently quoted a reference to show the answer; another pointed you to a reference where you can find the answer.<br><BR>\n" );
document.write( "An alternative to that approach is to do some math and get some practice in problem-solving skills.<br><BR>\n" );
document.write( "The figure has 20 faces, each of which is a kite.  The 20 kites together have a total of 20*4=80 edges.  An edge of the solid is where the edges of two faces meet.  The number of edges is therefore 80/2=40.<br><BR>\n" );
document.write( "Then use Euler's formula to determine the number of vertices:<br><BR>\n" );
document.write( "E = V+F-2<BR>\n" );
document.write( "40 = V+20-2<BR>\n" );
document.write( "V = 22<br><BR>\n" );
document.write( "ANSWER: this solid has 22 vertices.<br><BR>\n" );
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