document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=785437>Question 785437</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An open rectangular tank is made from a steel plate of area 1440msquared. Its length is twice its width. If the dept of the tank is 4m lesth than the width, find the length of the tank. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #477782 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=477782\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W ALIGN=MIDDLE  ALT=\"W\"   DISABLED_style= \"max-width:90%; height:auto;\" >= width in meters<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L=2W ALIGN=MIDDLE  ALT=\"L=2W\"   DISABLED_style= \"max-width:90%; height:auto;\" >= length in meters<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D=W-4 ALIGN=MIDDLE  ALT=\"D=W-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >= depth in meters<BR>\n" );
document.write( " <BR>\n" );
document.write( "Obviously, the entire 1440m^2 of the steel plate will be used, without wasting any, or stetching/deforming the material.<BR>\n" );
document.write( "That is probably far from realistic, but this is just a math problem.<BR>\n" );
document.write( "We cannot expect to work on the design, because we have not given enough information. The design is someone else's problem.<BR>\n" );
document.write( " <BR>\n" );
document.write( "The total surface of the tank includes the bottom, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=WL ALIGN=MIDDLE  ALT=\"WL\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5E2 ALIGN=MIDDLE  ALT=\"m%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "and the sides, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%28W%2BL%29D ALIGN=MIDDLE  ALT=\"2%28W%2BL%29D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5E2 ALIGN=MIDDLE  ALT=\"m%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "Our equation is<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=WL%2B2%28W%2BL%29D=1440 ALIGN=MIDDLE  ALT=\"WL%2B2%28W%2BL%29D=1440\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Since L and W came expressed in terms of W, we can substitute those expressions to get an equation in terms of W only:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W%282W%29%2B2%28W%2B2W%29%28W-4%29=1440 ALIGN=MIDDLE  ALT=\"W%282W%29%2B2%28W%2B2W%29%28W-4%29=1440\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W%5E2%2B2%283W%29%28W-4%29=1440 ALIGN=MIDDLE  ALT=\"2W%5E2%2B2%283W%29%28W-4%29=1440\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W%5E2%2B6W%28W-4%29=1440 ALIGN=MIDDLE  ALT=\"2W%5E2%2B6W%28W-4%29=1440\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W%5E2%2B6W%5E2-24W=1440 ALIGN=MIDDLE  ALT=\"2W%5E2%2B6W%5E2-24W=1440\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W%5E2%2B6W%5E2-24W-1440=0 ALIGN=MIDDLE  ALT=\"2W%5E2%2B6W%5E2-24W-1440=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8W%5E2-24W-1440=0 ALIGN=MIDDLE  ALT=\"8W%5E2-24W-1440=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Dividing both sides of the equal sign by 8, we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W%5E2-3W-180=0 ALIGN=MIDDLE  ALT=\"W%5E2-3W-180=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Factoring, we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28W-15%29%28W%2B12%29=0 ALIGN=MIDDLE  ALT=\"%28W-15%29%28W%2B12%29=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > with solutions <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=15 ALIGN=MIDDLE  ALT=\"W=15\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=-12 ALIGN=MIDDLE  ALT=\"W=-12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "We throw away <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W=-12 ALIGN=MIDDLE  ALT=\"W=-12\"   DISABLED_style= \"max-width:90%; height:auto;\" > because the width in meters cannot be a negative number.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w=15 ALIGN=MIDDLE  ALT=\"w=15\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=l=2W=2%2A15=highlight%2830%29 ALIGN=MIDDLE  ALT=\"l=2W=2%2A15=highlight%2830%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The length of the tank is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%2830m%29 ALIGN=MIDDLE  ALT=\"highlight%2830m%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );