document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=90435>Question 90435</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how many birds and lions do you have in your zoo? If there are 30 heads and 100 feet. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #65635 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=65635\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> how many birds and lions do you have in your zoo? If there are 30 heads and 100 feet.<BR>\n" );
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document.write( "Let # of birds be \"b\"; let number of lions be \"l\"<BR>\n" );
document.write( "Head equation: b+l   = 30<BR>\n" );
document.write( "Feet equation: 2b+4l = 100<BR>\n" );
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document.write( "l = 30-b<BR>\n" );
document.write( "Substitute to get:<BR>\n" );
document.write( "2b + 4(30-b) = 100<BR>\n" );
document.write( "Solve for b:<BR>\n" );
document.write( "2b+120-4b  = 100<BR>\n" );
document.write( "-2b = -20<BR>\n" );
document.write( "b = 10 (# of birds)<BR>\n" );
document.write( "l = 30 - 10 = 20 ( # of lions)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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