document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=892746>Question 892746</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A farmer is fencing a rectangular area for his farm using the straight portion of a river as one portion of the rectangle. If the farmer has 2400 feet of fence, find the dimension of the rectangle that gives the maximum area for the farm. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #541012 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=541012\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A farmer is fencing a rectangular area for his farm using the straight portion of a river as one portion of the rectangle. If the farmer has 2400 feet of fence, find the dimension of the rectangle that gives the maximum area for the farm.<BR>\n" );
document.write( "***<BR>\n" );
document.write( "let x=width (2 sides)<BR>\n" );
document.write( "2400-2x=length(1 side)<BR>\n" );
document.write( "area=length*width=x(2400-2x)=2400x-2x^2<BR>\n" );
document.write( "f(a)=-2x^2+2400<BR>\n" );
document.write( "complete the square:<BR>\n" );
document.write( "f(a)=-2(x^2-1200+360000)+720000<BR>\n" );
document.write( "f(a)=-2(x-600)^2+720000<BR>\n" );
document.write( "This is an equation of a parabola that opens down with vertex at (600,720,000)<BR>\n" );
document.write( "dimension of the rectangle that gives the maximum area of 720,000 sq ft for the farm:<BR>\n" );
document.write( "width=600 ft (2 sides)<BR>\n" );
document.write( "length=1200 ft (single side) </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );