document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=42285>Question 42285</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072549017/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Here it is copied and pasted exactly out of the book.\r<BR>\n" );
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document.write( "Construction. A garden area is 30 ft long and 20 ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400 ft^2, what is the width of the path?\r<BR>\n" );
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document.write( "Paul answered it as \r<BR>\n" );
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document.write( "400=(30+2x)(20+20)-(30*20)<BR>\n" );
document.write( "400 = 4x^2 + 100x<BR>\n" );
document.write( "x^2 + 25x - 100 = 0\r<BR>\n" );
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document.write( "Solve that and you get x = 3.5'\r<BR>\n" );
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document.write( "You replied with this can't be solved, so I am confused now. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #45818 by </B><A HREF=/tutors/aboutme.mpl?userid=303795><B>303795(602)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=303795><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=45818\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I note that you have two solutions for this problem but to me they are both incorrect.\r<BR>\n" );
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document.write( "The area for the garden is 30 m x 20 m. This is a total area of 600 square metres. If you get a final area of the garden as 400 square metres then the other 200 metres of the original garden area must be the path. The path is therefore on the inside of the 30 x 20 metre area. If the width of the path is x then the garden area inside the path must be (30-2x)(20-2x) which must be equal to 400 square metres<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2830-2x%29%2820-2x%29=400 ALIGN=MIDDLE  ALT=\"%2830-2x%29%2820-2x%29=400\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=600-100x%2B4x%5E2=400 ALIGN=MIDDLE  ALT=\"600-100x%2B4x%5E2=400\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Subtract 400 from each side of the equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=200-100x%2B4x%5E2-400=0 ALIGN=MIDDLE  ALT=\"200-100x%2B4x%5E2-400=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%5E2-100x%2B200=0 ALIGN=MIDDLE  ALT=\"4x%5E2-100x%2B200=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Divide through by 4<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2-25x%2B50=0 ALIGN=MIDDLE  ALT=\"x%5E2-25x%2B50=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The use of the quadratic equation then gives answers of x = 22.81 or x = 2.19<BR>\n" );
document.write( "Obviously the first is not a reasonable answer so the path width must be 2.19m.\r<BR>\n" );
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document.write( "Check (The length - the path is therefore 25.62 m and the width - the path is 15.62 m so the area inside the path is 400.18 square metres (a rounding error accounts for the small difference))\r<BR>\n" );
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document.write( " </SPAN>\n" );
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