document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=255837>Question 255837</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rectangle is 6cm long and 5 cm wide. When each dimension is increased by x cm, the area is tripled. Find the value of x.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188073 by </B><A HREF=/tutors/aboutme.mpl?userid=Greenfinch><B>Greenfinch(383)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Greenfinch><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=Greenfinch><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=188073\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Initially 6 x 5 = 30 sq cm<BR>\n" );
document.write( "In the new case (x + 6)(x + 5)=90<BR>\n" );
document.write( "x^2 + 11x + 30 = 90 or<BR>\n" );
document.write( "x^2 + 11x - 60 = 0<BR>\n" );
document.write( "(x - 4)(x + 15) = 0<BR>\n" );
document.write( "x = 4 or -15<BR>\n" );
document.write( "The number must be positive, so x=4<BR>\n" );
document.write( "this gives 10 and 9 cm which give an area of 90 cm sq<BR>\n" );
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