document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=351137>Question 351137</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is a mathematics problem which one of my cousin asked me yesterday.   He is in grade 4. However, I cannot help him because I am not good in maths.\r<BR>\n" );
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document.write( "The width of a rectangle  is  20  cm  more than  half the length.<BR>\n" );
document.write( "Its area  is   4800 sq.cm.<BR>\n" );
document.write( "Find its width. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #250981 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=250981\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Start with the formula for the area of a rectangle:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+L%2AW ALIGN=MIDDLE  ALT=\"A+=+L%2AW\"   DISABLED_style= \"max-width:90%; height:auto;\" > Where L = length and W = width.<BR>\n" );
document.write( "The area, A, is given as A = 4800 sq.cm.<BR>\n" );
document.write( "The width, W, is given as:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W+=+%281%2F2%29L%2B20 ALIGN=MIDDLE  ALT=\"W+=+%281%2F2%29L%2B20\"   DISABLED_style= \"max-width:90%; height:auto;\" > \"The width ... is 20cm more than half the length.\"<BR>\n" );
document.write( "Let's express the above in terms of the length, L.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W+=+%281%2F2%29L%2B20 ALIGN=MIDDLE  ALT=\"W+=+%281%2F2%29L%2B20\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply through by 2 to clear the fraction.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W+=+L%2B40 ALIGN=MIDDLE  ALT=\"2W+=+L%2B40\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 40 from both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W-40+=+L ALIGN=MIDDLE  ALT=\"2W-40+=+L\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now substitute this into the formula for L.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+L%2AW ALIGN=MIDDLE  ALT=\"A+=+L%2AW\"   DISABLED_style= \"max-width:90%; height:auto;\" > Substitute A = 4800, L = 2W-40<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4800+=+%282W-40%29%2AW ALIGN=MIDDLE  ALT=\"4800+=+%282W-40%29%2AW\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4800+=+2W%5E2-40W ALIGN=MIDDLE  ALT=\"4800+=+2W%5E2-40W\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now subtract 4800 from both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2W%5E2-40W-4800+=+0 ALIGN=MIDDLE  ALT=\"2W%5E2-40W-4800+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide by 2 to simplify a bit.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W%5E2-20W-2400+=+0 ALIGN=MIDDLE  ALT=\"W%5E2-20W-2400+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Factor this quadratic equation.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28W%2B40%29%28W-60%29+=+0 ALIGN=MIDDLE  ALT=\"%28W%2B40%29%28W-60%29+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Apply the zero product rule.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W%2B40+=+0 ALIGN=MIDDLE  ALT=\"W%2B40+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W-60+=+0 ALIGN=MIDDLE  ALT=\"W-60+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > so...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W+=+-40 ALIGN=MIDDLE  ALT=\"W+=+-40\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=W+=+60 ALIGN=MIDDLE  ALT=\"W+=+60\"   DISABLED_style= \"max-width:90%; height:auto;\" > Discard the negative solution as width is a positive quantity.<BR>\n" );
document.write( "The width is 60cm.<BR>\n" );
document.write( "Note: This is certainly well beyond grade 4 level math in american schools. </SPAN>\n" );
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