document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=111796>Question 111796</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have a rectangular pen with an area of 2400 square meters. I remember that the width of the pen is 20 meters greater than the length. Find the length and width of the rectangular pen. I used the formula Let w = the width; Let w + 3 = the length; Area = lw and the instructor said that it was not a proper function because it only contained one variable. What am I doing wrong?\r<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 #81557 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20849)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=81557\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  if the width of the pen is 20 meters greater than the length, you can't have w + 3 = the length; \r<BR>\n" );
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document.write( "you need to write:\r<BR>\n" );
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document.write( "the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=width=+W ALIGN=MIDDLE  ALT=\"width=+W\"   DISABLED_style= \"max-width:90%; height:auto;\" >  of the pen is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20+m+ ALIGN=MIDDLE  ALT=\"20+m+\"   DISABLED_style= \"max-width:90%; height:auto;\" > greater than the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+length=+L ALIGN=MIDDLE  ALT=\"+length=+L\"   DISABLED_style= \"max-width:90%; height:auto;\" >…....=> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=+L+%2B+20m ALIGN=MIDDLE  ALT=\"W=+L+%2B+20m\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+A+=+2400++m%5E2 ALIGN=MIDDLE  ALT=\"+A+=+2400++m%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+A+=+W+L++ ALIGN=MIDDLE  ALT=\"+A+=+W+L++\"   DISABLED_style= \"max-width:90%; height:auto;\" >…..substitute  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W ALIGN=MIDDLE  ALT=\"W\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A ALIGN=MIDDLE  ALT=\"A\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2400++m%5E2+=+%28L+%2B+20m%29++L++ ALIGN=MIDDLE  ALT=\"+2400++m%5E2+=+%28L+%2B+20m%29++L++\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2400++m%5E2+=+L%5E2+%2B+L20m+++ ALIGN=MIDDLE  ALT=\"+2400++m%5E2+=+L%5E2+%2B+L20m+++\"   DISABLED_style= \"max-width:90%; height:auto;\" >………move <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2400++m%5E2+++ ALIGN=MIDDLE  ALT=\"2400++m%5E2+++\"   DISABLED_style= \"max-width:90%; height:auto;\" > to the right\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0+=+L%5E2+%2B+L20m++-+2400++m%5E2++ ALIGN=MIDDLE  ALT=\"+0+=+L%5E2+%2B+L20m++-+2400++m%5E2++\"   DISABLED_style= \"max-width:90%; height:auto;\" >………\r<BR>\n" );
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document.write( "Use quadratic formula to find only positive value for the length <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L ALIGN=MIDDLE  ALT=\"L\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=%28-20+%2B+sqrt+%2820%5E2+-4%2A1%2A%28-2400%29+%29%29+%2F+%282%2A1%29 ALIGN=MIDDLE  ALT=\"L%5B1%5D=%28-20+%2B+sqrt+%2820%5E2+-4%2A1%2A%28-2400%29+%29%29+%2F+%282%2A1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=%28-20+%2B+sqrt+%28400%5E2+%2B+9600%29%29+%2F+2 ALIGN=MIDDLE  ALT=\"L%5B1%5D=%28-20+%2B+sqrt+%28400%5E2+%2B+9600%29%29+%2F+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=%28-20+%2B+sqrt+%2810000%29%29+%2F+2 ALIGN=MIDDLE  ALT=\"L%5B1%5D=%28-20+%2B+sqrt+%2810000%29%29+%2F+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=%28-20+%2B+100%29+%2F+2 ALIGN=MIDDLE  ALT=\"L%5B1%5D=%28-20+%2B+100%29+%2F+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=+80+%2F+2 ALIGN=MIDDLE  ALT=\"L%5B1%5D=+80+%2F+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5B1%5D=+40m ALIGN=MIDDLE  ALT=\"L%5B1%5D=+40m\"   DISABLED_style= \"max-width:90%; height:auto;\" >…….the  length\r<BR>\n" );
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document.write( "Now find the width\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=+L+%2B+20m ALIGN=MIDDLE  ALT=\"W=+L+%2B+20m\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=+40m%2B+20m ALIGN=MIDDLE  ALT=\"W=+40m%2B+20m\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=+60m ALIGN=MIDDLE  ALT=\"W=+60m\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "Check:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+A+=+W+%2AL++ ALIGN=MIDDLE  ALT=\"+A+=+W+%2AL++\"   DISABLED_style= \"max-width:90%; height:auto;\" >…..\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+A+=+40m+%2A+60m++ ALIGN=MIDDLE  ALT=\"+A+=+40m+%2A+60m++\"   DISABLED_style= \"max-width:90%; height:auto;\" >…..\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+A+=+2400m+%5E2+ ALIGN=MIDDLE  ALT=\"+A+=+2400m+%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >…..\r<BR>\n" );
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