document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=354595>Question 354595</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rancher needs two adjacent corrals, one for cattle and one for sheep. If a river forms one side of the corrals and 240 yd of fencing is available, what is the largest total area that can be enclosed?\r<BR>\n" );
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document.write( "Perimeter = y + 3x<BR>\n" );
document.write( "A = x * y\r<BR>\n" );
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document.write( "A = x(-3x+240)<BR>\n" );
document.write( "A = -3x^2+240x<BR>\n" );
document.write( "=-3(x^2-80x)<BR>\n" );
document.write( "=-3(x^2-80x-40^2)+4800<BR>\n" );
document.write( "=-3(x-40)^2+4800\r<BR>\n" );
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document.write( "Maximum total area is 4800 yards\r<BR>\n" );
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document.write( "Did I solve it correctly? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #253368 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=253368\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A rancher needs two adjacent corrals, one for cattle and one for sheep. If a river forms one side of the corrals and 240 yd of fencing is available, what is the largest total area that can be enclosed? <BR>\n" );
document.write( "Perimeter = y + 3x<BR>\n" );
document.write( "A = x * y <BR>\n" );
document.write( "A = x(-3x+240)<BR>\n" );
document.write( "A = -3x^2+240x<BR>\n" );
document.write( "=-3(x^2-80x)<BR>\n" );
document.write( "=-3(x^2-80x-40^2)+4800<BR>\n" );
document.write( "=-3(x-40)^2+4800 <BR>\n" );
document.write( "Maximum total area is 4800 yards <BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "If both corrals have one side on the river:<BR>\n" );
document.write( "2x + 2y = 240 --> y = 120-x<BR>\n" );
document.write( "Area = x*2y = 240x - 2x^2<BR>\n" );
document.write( "A parabola with the line of symmetry of x = -b/2a<BR>\n" );
document.write( "x = -240/(-4) = 60<BR>\n" );
document.write( "--> y = 60<BR>\n" );
document.write( "Area = 60*120 = 7200 sq yds<BR>\n" );
document.write( " </SPAN>\n" );
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