document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=579237>Question 579237</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A lawn is 90 feet long and 40 feet wide. By cutting along the perimeter, how wide is this border if 1/3 of the grass is cut?\r<BR>\n" );
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document.write( "More info: provided solution is 5 feet.  Student says answer must be derived by using quadratic formula.\r<BR>\n" );
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document.write( "X=width of the border<BR>\n" );
document.write( "2(90)(x)+2(40)(x)=(90 times 40)/3\r<BR>\n" );
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document.write( "Which then does not result in a constant for a to be used in the quadratic formula.  B is 260 and c is negative 1200.  Since the constant a is zero, i get a divide by zero using the quadratic formula which means to me the answer is infinite but the provided answer is 5.  I have made an error but i can't find it.  Please advise. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #370910 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16949)</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=370910\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Area of garden = 90 * 40 ft = 3600 sq. ft\r<BR>\n" );
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document.write( "1/3 of this area is cut = 1200 sq. ft\r<BR>\n" );
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document.write( "Let the uniform width be x<BR>\n" );
document.write( "so the reduced length = 90-2x<BR>\n" );
document.write( "reduced width = 40-2x\r<BR>\n" );
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document.write( "area of this portion is ( 90-2x)((40-2x)\r<BR>\n" );
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document.write( "Total area - reduced area = area of the grass cut\r<BR>\n" );
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document.write( "3600-(90-2x)(40-2x)= 1200<BR>\n" );
document.write( "(90-2x)(40-2x)= 3600-1200<BR>\n" );
document.write( "90(40-2x)-2x(40-2x) = 2400<BR>\n" );
document.write( "3600-180x-80x+4x^2=2400<BR>\n" );
document.write( "4x^2-260x+1200=0<BR>\n" );
document.write( "/4<BR>\n" );
document.write( "x^2-65x+300=0\r<BR>\n" );
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document.write( "x^2-60x-5x+300=0\r<BR>\n" );
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document.write( "x(x-60)-5(x-60)=0<BR>\n" );
document.write( "(x-60)(x-5)=0<BR>\n" );
document.write( "x= 60 not possible<BR>\n" );
document.write( "x= 5 ft the width \r<BR>\n" );
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document.write( "m.ananth@hotmail.ca\r<BR>\n" );
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document.write( " </SPAN>\n" );
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