document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1087632>Question 1087632</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The local park measures 60 m by 50 m. Part of the park is torn up to install a sidewalk of uniform width about it, reducing the area of the park itself by 321 m2. How wide is the sidewalk? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #701979 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=701979\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let l be the length of the internal rectangle and w be the width of the internal rectangle<BR>\n" );
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document.write( "1)  (l+2x) * (w+2x) = 3000<BR>\n" );
document.write( "2)  2(l+2x) + 2(w+2x) = 220<BR>\n" );
document.write( "3)  l * w = 3000 - 321 = 2679<BR>\n" );
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document.write( "expand equation 1 by multiplication of left side of =<BR>\n" );
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document.write( "lw +2xw +2xl +4x^2 = 3000<BR>\n" );
document.write( "4)  4x^2 +2x(w+l) = 321<BR>\n" );
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document.write( "use equation 2 to get expression for w+l<BR>\n" );
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document.write( "l +w + 4x = 110<BR>\n" );
document.write( "l +w = 110-4x<BR>\n" );
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document.write( "substitute for l+w in equation 4<BR>\n" );
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document.write( "4x^2 +2x(110-4x) = 321<BR>\n" );
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document.write( "4x^2 +220x -8x^2 = 321<BR>\n" );
document.write( "4x^2 -220x +321 = 0<BR>\n" );
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document.write( "use quadratic formula to solve for x<BR>\n" );
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document.write( "x = (-(-220) + square root((-220)^2 -4*4*321)) / 2(4) = 53.5<BR>\n" );
document.write( "x = (-(-220) - square root((-220)^2 -4*4*321)) / 2(4) = 1.5<BR>\n" );
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document.write( "we accept x = 1.5 m<BR>\n" );
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document.write( "the sidewalk is 1.5 m wide<BR>\n" );
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document.write( " </SPAN>\n" );
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