document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=581689>Question 581689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Completing the Square: Angelique wants to have a rug that is 9 feet long and 7 feet wide in her bedroom. The rug will cover the whole floor except a border that is x feet wide. The area of her room is 168 square feet. Find the width of the border, x. Round your answer to the nearest tenth of a foot. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #371815 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=371815\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Completing the Square: Angelique wants to have a rug that is 9 feet long and 7 feet wide in her bedroom.<BR>\n" );
document.write( " The rug will cover the whole floor except a border that is x feet wide.<BR>\n" );
document.write( " The area of her room is 168 square feet.<BR>\n" );
document.write( " Find the width of the border, x. Round your answer to the nearest tenth of a foot.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "From the information given we know the overall dimensions of the room is:<BR>\n" );
document.write( "(2x+9) by (2x+7)<BR>\n" );
document.write( "The area of the room:<BR>\n" );
document.write( "(2x+9)(2x+7) = 168<BR>\n" );
document.write( "FOIL<BR>\n" );
document.write( "4x^2 + 14x + 18x + 63 = 168<BR>\n" );
document.write( "4x^2 + 32x + 63 - 168 = 0<BR>\n" );
document.write( "4x^2 + 32x - 105 = 0<BR>\n" );
document.write( "Solve by completing the square, we want the coefficient of x^2 to be 1, divide equation by 4<BR>\n" );
document.write( "x^2 + 8x - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=105%2F4 ALIGN=MIDDLE  ALT=\"105%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 0<BR>\n" );
document.write( "x^2 + 8x + ___ = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=105%2F4 ALIGN=MIDDLE  ALT=\"105%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Find the value that will complete the square (8/2)^2 = 16, add to both sides<BR>\n" );
document.write( "x^2 + 8x + 16 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=105%2F4 ALIGN=MIDDLE  ALT=\"105%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 16<BR>\n" );
document.write( "x^2 + 8x + 16 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=105%2F4 ALIGN=MIDDLE  ALT=\"105%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=64%2F4 ALIGN=MIDDLE  ALT=\"64%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x^2 + 8x + 16 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=169%2F4 ALIGN=MIDDLE  ALT=\"169%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "(x+4)^2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=169%2F4 ALIGN=MIDDLE  ALT=\"169%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "Find the square root of both side<BR>\n" );
document.write( "x + 4 = +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28169%2F4%29 ALIGN=MIDDLE  ALT=\"sqrt%28169%2F4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = -4 + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F2 ALIGN=MIDDLE  ALT=\"13%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2.5 ft<BR>\n" );
document.write( "and<BR>\n" );
document.write( "x = -4 - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F2 ALIGN=MIDDLE  ALT=\"13%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -10.5<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Obviously, x = 2.5 is the reasonable answer<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "See if this checks out, find the area (2x = 5)<BR>\n" );
document.write( "(5+9)(5+7) = 168<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );