document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=168739>Question 168739</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the area of a square is 21 more than the perimeter. Find the length of a side </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #124384 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=124384\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"the area of a square is 21 more than the perimeter\" ----> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=P%2B21 ALIGN=MIDDLE  ALT=\"A=P%2B21\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Remember, the area of a square is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=s%5E2 ALIGN=MIDDLE  ALT=\"A=s%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and the perimeter of a square is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=4s ALIGN=MIDDLE  ALT=\"P=4s\"   DISABLED_style= \"max-width:90%; height:auto;\" >  where \"s\" is the side length\r<BR>\n" );
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document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=P%2B21 ALIGN=MIDDLE  ALT=\"A=P%2B21\"   DISABLED_style= \"max-width:90%; height:auto;\" > becomes <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%5E2=4s%2B21 ALIGN=MIDDLE  ALT=\"s%5E2=4s%2B21\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%5E2-4s-21=0 ALIGN=MIDDLE  ALT=\"s%5E2-4s-21=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 4s from both sides. Subtract 21 from both sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28s-7%29%28s%2B3%29=0 ALIGN=MIDDLE  ALT=\"%28s-7%29%28s%2B3%29=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Factor the left side (note: if you need help with factoring, check out this <a  rel=nofollow HREF=http://www.algebra.com/algebra/homework/playground/change-this-name4450.solver>solver</a>)\r<BR>\n" );
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document.write( "Now set each factor equal to zero:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s-7=0 ALIGN=MIDDLE  ALT=\"s-7=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > or  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%2B3=0 ALIGN=MIDDLE  ALT=\"s%2B3=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s=7 ALIGN=MIDDLE  ALT=\"s=7\"   DISABLED_style= \"max-width:90%; height:auto;\" > or  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s=-3 ALIGN=MIDDLE  ALT=\"s=-3\"   DISABLED_style= \"max-width:90%; height:auto;\" >    Now solve for s in each case\r<BR>\n" );
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document.write( "Now discard the solution <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s=-3 ALIGN=MIDDLE  ALT=\"s=-3\"   DISABLED_style= \"max-width:90%; height:auto;\" > since a negative side length does not make sense.\r<BR>\n" );
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document.write( "So the answer is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s=7 ALIGN=MIDDLE  ALT=\"s=7\"   DISABLED_style= \"max-width:90%; height:auto;\" > which means that the length of the side of the square is 7 units </SPAN>\n" );
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