document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=214015>Question 214015</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the geatest possible area of a rectangle if its perimeter is 30 cm<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 #161666 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=161666\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the sides are <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w ALIGN=MIDDLE  ALT=\"w\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2h+%2B+2w+=+30 ALIGN=MIDDLE  ALT=\"2h+%2B+2w+=+30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2w+=+30+-+2h ALIGN=MIDDLE  ALT=\"2w+=+30+-+2h\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w+=+%281%2F2%29%2A%2830+-+2h%29 ALIGN=MIDDLE  ALT=\"w+=+%281%2F2%29%2A%2830+-+2h%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+w%2Ah ALIGN=MIDDLE  ALT=\"A+=+w%2Ah\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%281%2F2%29%2A%2830+-+2h%29%2Ah ALIGN=MIDDLE  ALT=\"A+=+%281%2F2%29%2A%2830+-+2h%29%2Ah\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%281%2F2%29%2A%2830h+-+2h%5E2%29 ALIGN=MIDDLE  ALT=\"A+=+%281%2F2%29%2A%2830h+-+2h%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+-h%5E2+%2B+15h ALIGN=MIDDLE  ALT=\"A+=+-h%5E2+%2B+15h\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The - sign tells me this is a parabola with<BR>\n" );
document.write( "a peak at the top, or a maximum<BR>\n" );
document.write( "The maximum occurs exactly between the<BR>\n" );
document.write( "roots, or at }<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-b%2F%282a%29 ALIGN=MIDDLE  ALT=\"-b%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+15 ALIGN=MIDDLE  ALT=\"b+=+15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+-1 ALIGN=MIDDLE  ALT=\"a+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5Bmax%5D+=+-b%2F%282a%29 ALIGN=MIDDLE  ALT=\"h%5Bmax%5D+=+-b%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5Bmax%5D+=+-15%2F-2 ALIGN=MIDDLE  ALT=\"h%5Bmax%5D+=+-15%2F-2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%5Bmax%5D+=+7.5 ALIGN=MIDDLE  ALT=\"h%5Bmax%5D+=+7.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w+=+%281%2F2%29%2A%2830+-+2h%29 ALIGN=MIDDLE  ALT=\"w+=+%281%2F2%29%2A%2830+-+2h%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w+=+%281%2F2%29%2A%2830+-+15%29 ALIGN=MIDDLE  ALT=\"w+=+%281%2F2%29%2A%2830+-+15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w+=+7.5 ALIGN=MIDDLE  ALT=\"w+=+7.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "A 7.5 x 7.5 rectangle, or a square, has the max area<BR>\n" );
document.write( "which is<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%5E2+=+56.25 ALIGN=MIDDLE  ALT=\"7.5%5E2+=+56.25\"   DISABLED_style= \"max-width:90%; height:auto;\" > cm2<BR>\n" );
document.write( "You can prove this by changing the square slightly<BR>\n" );
document.write( "and keep the perimeter the same, say<BR>\n" );
document.write( "7.4 x 7.6<BR>\n" );
document.write( "perimeter = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2A7.4+%2B+2%2A7.6+=+14.8+%2B+15.2 ALIGN=MIDDLE  ALT=\"2%2A7.4+%2B+2%2A7.6+=+14.8+%2B+15.2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14.8+%2B+15.2+=+30 ALIGN=MIDDLE  ALT=\"14.8+%2B+15.2+=+30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+7.4%2A7.6 ALIGN=MIDDLE  ALT=\"A+=+7.4%2A7.6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+56.24 ALIGN=MIDDLE  ALT=\"A+=+56.24\"   DISABLED_style= \"max-width:90%; height:auto;\" > (just a little smaller than 56.25)<BR>\n" );
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