document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1111156>Question 1111156</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I really would appreciate your help understanding problems like the one below:\r<BR>\n" );
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document.write( "Marie Mulroney has a rectangular board 12 inches by 16 inches around which she wants to put a uniform border of shells. If she had enough shells for a border whose area is 128 square inches, determine the width of the border.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #726170 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=726170\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There is a border on both sides of the 12 in<BR>\n" );
document.write( "side, so that each side is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+12+%2B+2x+ ALIGN=MIDDLE  ALT=\"+12+%2B+2x+\"   DISABLED_style= \"max-width:90%; height:auto;\" > in long<BR>\n" );
document.write( "Also, there is a border on each side of the<BR>\n" );
document.write( "16 in side, so this side is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+16+%2B+2x+ ALIGN=MIDDLE  ALT=\"+16+%2B+2x+\"   DISABLED_style= \"max-width:90%; height:auto;\" > in long<BR>\n" );
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document.write( "Add up the inside area and the ares of the border.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+12%2A16+%2B+128+=+192+%2B+128+ ALIGN=MIDDLE  ALT=\"+12%2A16+%2B+128+=+192+%2B+128+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+192+%2B+128+=+320+ ALIGN=MIDDLE  ALT=\"+192+%2B+128+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" > in2<BR>\n" );
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document.write( "Now I can say:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+12+%2B+2x+%29%2A%28+16+%2B+2x+%29+=+320+ ALIGN=MIDDLE  ALT=\"+%28+12+%2B+2x+%29%2A%28+16+%2B+2x+%29+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+192+%2B+32x+%2B+24x+%2B+4x%5E2+=+320+ ALIGN=MIDDLE  ALT=\"+192+%2B+32x+%2B+24x+%2B+4x%5E2+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4x%5E2+%2B+56x+-+128+=+0+ ALIGN=MIDDLE  ALT=\"+4x%5E2+%2B+56x+-+128+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%5E2+%2B+14x+-+32+=+0+ ALIGN=MIDDLE  ALT=\"+x%5E2+%2B+14x+-+32+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+x+%2B+16+%29%2A%28+x+-+2+%29+=+0+ ALIGN=MIDDLE  ALT=\"+%28+x+%2B+16+%29%2A%28+x+-+2+%29+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" > ( by observation )<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x+=+2+ ALIGN=MIDDLE  ALT=\"+x+=+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > ( can only use the positve result )<BR>\n" );
document.write( "The width of the border is 2 in<BR>\n" );
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document.write( "check:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+12+%2B+2%2A2+%29%2A%28+16+%2B+2%2A2+%29+=+320+ ALIGN=MIDDLE  ALT=\"+%28+12+%2B+2%2A2+%29%2A%28+16+%2B+2%2A2+%29+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+16%2A20+=+320+ ALIGN=MIDDLE  ALT=\"+16%2A20+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+320+=+320+ ALIGN=MIDDLE  ALT=\"+320+=+320+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK<BR>\n" );
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