document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=255888>Question 255888</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A farmer has 1000 feet of fence.  He wants to enclose a pasture bordering on long straight river where no fence is needed.  Find the area of the largest such enclosure.  \r<BR>\n" );
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document.write( "Thank you for help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188096 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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=188096\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We have two formulas:<BR>\n" );
document.write( "(i) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P+=+2x+%2B+y ALIGN=MIDDLE  ALT=\"P+=+2x+%2B+y\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where p =1000. Note we only have 3 sides.<BR>\n" );
document.write( "(ii) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+xy ALIGN=MIDDLE  ALT=\"A+=+xy\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "From (i) we get<BR>\n" );
document.write( "(iii) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1000+=+2x+%2B+y ALIGN=MIDDLE  ALT=\"1000+=+2x+%2B+y\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Solve (iii) for y to get<BR>\n" );
document.write( "(iv) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+1000-2x ALIGN=MIDDLE  ALT=\"y+=+1000-2x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "substitute (iv) into (ii) to get<BR>\n" );
document.write( "(v) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+x%281000-2x%29 ALIGN=MIDDLE  ALT=\"A+=+x%281000-2x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "which is<BR>\n" );
document.write( "(vi) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+-2x%5E2+%2B+1000x ALIGN=MIDDLE  ALT=\"A+=+-2x%5E2+%2B+1000x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "set -2x^2 + 1000x = 0  and create vertex form as<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-250%29%5E2+%2B+125000 ALIGN=MIDDLE  ALT=\"%28x-250%29%5E2+%2B+125000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "so the max area is 125,000 sq. ft. </SPAN>\n" );
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