document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1081031>Question 1081031</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find two real numbers  (x) and (y) such that 2x+y=80 and A=xy is maximum </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #695100 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=695100\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y=80-2x<BR>\n" );
document.write( "substitute <BR>\n" );
document.write( "A=x(80-2x)=80x-2x^2<BR>\n" );
document.write( "derivative is 80-4x<BR>\n" );
document.write( "set that equal to 0 and 80=4x<BR>\n" );
document.write( "x=20<BR>\n" );
document.write( "y=40<BR>\n" );
document.write( "That adds to 80 and the product is 800.<BR>\n" );
document.write( "Try x=19 and y=42, product is 798<BR>\n" );
document.write( "try x=21 and y=38, product is 798<BR>\n" );
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