document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=861680>Question 861680</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rectangle is drawn so that the width is 4 feet shorter than the length. The area of the rectangle is 12 square feet. Find the length of the rectangle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #519167 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=519167\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Common enough to be worth generalizing.\r<BR>\n" );
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document.write( "width w, length L.<BR>\n" );
document.write( "Width is soe k feet shorter than length, or w=L-k.<BR>\n" );
document.write( "Area is given, and may be called A.<BR>\n" );
document.write( "The unknown variables are L and w.<BR>\n" );
document.write( "(A=12 and k=4).\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=wL=A ALIGN=MIDDLE  ALT=\"wL=A\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28L-k%29L=A ALIGN=MIDDLE  ALT=\"%28L-k%29L=A\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L%5E2-kL-A=0 ALIGN=MIDDLE  ALT=\"L%5E2-kL-A=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Note that your given values for area and for k may render the quadratic equation in L as factorable.  In GENERAL, you cannot rely on factorizability.<BR>\n" );
document.write( "General Solution to Quadratic Equation gives for L,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L=%28k%2Bsqrt%28k%5E2-4%28-A%29%29%29%2F2 ALIGN=MIDDLE  ALT=\"L=%28k%2Bsqrt%28k%5E2-4%28-A%29%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28highlight_green%28L=%28k%2Bsqrt%28k%5E2%2B4A%29%29%2F2%29%29 ALIGN=MIDDLE  ALT=\"highlight%28highlight_green%28L=%28k%2Bsqrt%28k%5E2%2B4A%29%29%2F2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "You can substitute the values for A and k to compute L. </SPAN>\n" );
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