document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=288985>Question 288985</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A uniform-width boardwalk is built around the inside edge of a rectangular parkland that is 10m by 15m. If the boardwalk takes 20% of the lot, how wide is the boardwalk to the nearest centimetre? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #209386 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=209386\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A uniform-width boardwalk is built around the inside edge of a rectangular parkland that is 10m by 15m. If the boardwalk takes 20% of the lot, how wide is the boardwalk to the nearest centimetre?\r<BR>\n" );
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document.write( "The area of parkland = 10* 15 = 150 sq. meters\r<BR>\n" );
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document.write( "Boardwalk takes 20% of 150\r<BR>\n" );
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document.write( "=20/100 * 150<BR>\n" );
document.write( "=30 sq. mtrs.\r<BR>\n" );
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document.write( "let the width of the boardwalk be x\r<BR>\n" );
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document.write( "the length of parkland excluding width of board walk = 15-2x\r<BR>\n" );
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document.write( "width will be 10-2x\r<BR>\n" );
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document.write( "150 - (15-2x)(10-2x)=30\r<BR>\n" );
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document.write( "150 -{ 150 -30x-20x+4x^2}=30\r<BR>\n" );
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document.write( "150-150+50x-4x^2-30=0\r<BR>\n" );
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document.write( "4x^2-50x-30=0\r<BR>\n" );
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document.write( "taking the roots of the equation \r<BR>\n" );
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document.write( "x1= 50+sqrt(2500+480)  / 8\r<BR>\n" );
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document.write( "=50+sqrt2980 /8\r<BR>\n" );
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document.write( "=13.07   Or 13\r<BR>\n" );
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document.write( "x2 will be negative \r<BR>\n" );
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document.write( "so 13 meters is the width of the board walk\r<BR>\n" );
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document.write( " </SPAN>\n" );
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