document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=375207>Question 375207</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the sides of a rectangle whose perimeter is 40 and diagonal is 18? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #266829 by </B><A HREF=/tutors/aboutme.mpl?userid=unlockmath><B>unlockmath(1688)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=unlockmath><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=unlockmath><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=266829\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hello, <BR>\n" );
document.write( "Lets have x be the width and y be the length. We can set up two equations as:<BR>\n" );
document.write( "2x+2y=40<BR>\n" );
document.write( "x^2+y^2=18^2<BR>\n" );
document.write( "With the first equation lets do this:<BR>\n" );
document.write( "y=20-x<BR>\n" );
document.write( "Now substitute this into the second equation:<BR>\n" );
document.write( "x^2+(-x+20)^2=18^2<BR>\n" );
document.write( "This can be rewritten as:<BR>\n" );
document.write( "x^2+x^2-40x+400=324<BR>\n" );
document.write( "Subtract 324 from both sides and combine like terms to get:<BR>\n" );
document.write( "2x^2-40x+76=0<BR>\n" );
document.write( "Rewritten as:<BR>\n" );
document.write( "2(x^2-20x+38)=0<BR>\n" );
document.write( "From here you can use the quadratic formula to solve for x and then you can solve for y. <BR>\n" );
document.write( "Got it?<BR>\n" );
document.write( "RJ<BR>\n" );
document.write( "www.math-unlock.com </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );