document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=520392>Question 520392</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The area of a rectangular lot 80m by 100m is to be increased by 4000m^2. The length and the width will be increased by the same amount. What are the dimensions of the larger lot? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #346077 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=346077\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Area = Length * Width<BR>\n" );
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document.write( "A = 80 m * 100 m<BR>\n" );
document.write( "A = 8000 m^2<BR>\n" );
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document.write( "The area is increased by 4000...<BR>\n" );
document.write( "A = 8000 + 4000 m^2<BR>\n" );
document.write( "A = 12000<BR>\n" );
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document.write( "L and W will be increased by the same amount.<BR>\n" );
document.write( "What are the new dimensions?<BR>\n" );
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document.write( "x = the amount of increase<BR>\n" );
document.write( "80+x = new dimension<BR>\n" );
document.write( "100+x = new dimension<BR>\n" );
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document.write( "(80+x)(100+x) = 12000<BR>\n" );
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document.write( "use FOIL<BR>\n" );
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document.write( "8000 +80x +100x + x^2 = 12000<BR>\n" );
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document.write( "rearrange<BR>\n" );
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document.write( "x^2 + 180x + 8000 -12000 = 0<BR>\n" );
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document.write( "x^2  +180x -4000 = 0<BR>\n" );
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document.write( "factor<BR>\n" );
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document.write( "(x+200)(x-20) = 0<BR>\n" );
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document.write( "check using FOIL<BR>\n" );
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document.write( "x^2 -20x +200x -4000 = 0<BR>\n" );
document.write( "OK<BR>\n" );
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document.write( "x = -200 or 20<BR>\n" );
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document.write( "Negative length and width are nonsense, so x = 20 is the only reasonable solution.<BR>\n" );
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document.write( "Re-read the question to be sure you answer it.<BR>\n" );
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document.write( "Answer:  The dimensions of the new lot are 100 by 120 m.<BR>\n" );
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document.write( "Always check your answer.<BR>\n" );
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document.write( "100*120 = 12000 = 8000 + 4000<BR>\n" );
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document.write( "Done. </SPAN>\n" );
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