document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=622272>Question 622272</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Al has collected 60 insects, all of which are spiders,<BR>\n" );
document.write( "dragonflies, and cicadas. Al counts 380 legs, and 140<BR>\n" );
document.write( "wings altogether. How many insects are there in each<BR>\n" );
document.write( "kind?\r<BR>\n" );
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document.write( "i want to solve this using equations<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #391248 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=391248\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Al has collected 60 insects, all of which are spiders,<BR>\n" );
document.write( "dragonflies, and cicadas. Al counts 380 legs, and 140<BR>\n" );
document.write( "wings altogether. How many insects are there in each<BR>\n" );
document.write( "kind?<BR>\n" );
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document.write( "c + d + s = 60 (# of creatures)<BR>\n" );
document.write( "6c + 6d + 8s = 380 (# of legs)<BR>\n" );
document.write( "2c + 4d = 140 (# of wings)<BR>\n" );
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document.write( "2c + 4d = 140 (# of wings)<BR>\n" );
document.write( "c + 2d = 70<BR>\n" );
document.write( "c = 70 - 2d<BR>\n" );
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document.write( "Sub for c in eqns 1 & 2<BR>\n" );
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document.write( "c + d + s = 60 (# of creatures)<BR>\n" );
document.write( "70 - 2d + d + s = 60<BR>\n" );
document.write( "-d + s = -10<BR>\n" );
document.write( "----<BR>\n" );
document.write( "6c + 6d + 8s = 380 (# of legs)<BR>\n" );
document.write( "6(70 - 2d) + 6d + 8s = 380<BR>\n" );
document.write( "420 - 6d + 8s = 380<BR>\n" );
document.write( "-3d + 4s = -20<BR>\n" );
document.write( "------<BR>\n" );
document.write( "-d + s = -10<BR>\n" );
document.write( "3d - 3s = 30<BR>\n" );
document.write( "-3d + 4s = -20<BR>\n" );
document.write( "----------------- Add<BR>\n" );
document.write( "s = 10<BR>\n" );
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document.write( "d = 20<BR>\n" );
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document.write( "c = 30<BR>\n" );
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document.write( "Dragonflies have 4 wings.<BR>\n" );
document.write( "Spiders are not insects.\r<BR>\n" );
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