document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=463891>Question 463891</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I just finished a math exam and theres one question that I just couldn't figure out. It went like this: \"A rectangular field has an 800m long fence around the perimeter. The area of the field is 37500m^2. What are the diemensions of the field.\" I think im supposed to use Substitution so I wrote the formulas I know that relate to the question and I plugged in the information from the question into the equation so it was like this: \"P(perimeter)=2*L(length)+2*width & A(area)=L*W. After this I dont know what to do. I can eliminate be the operations are different so the only option is to change an equation to isolate a variable to substitute it into the next equation but I don't know. No hurry gettin back to me the exams already done im just asking to ease my mind </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #317744 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=317744\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know the perimeter is 800 m and the area is 37500m^2, so\r<BR>\n" );
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document.write( "800 = 2L + 2W --> L + W = 400\r<BR>\n" );
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document.write( "LW = 37500\r<BR>\n" );
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document.write( "From the equation L + W = 400 we can isolate L and say L = 400 - W. Plug this into the expression for area:\r<BR>\n" );
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document.write( "(400-W)W = 37500\r<BR>\n" );
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document.write( "-W^2 + 400W - 37500 = 0\r<BR>\n" );
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document.write( "W^2 - 400W + 37500 = 0\r<BR>\n" );
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document.write( "By factoring or by the quadratic formula, we get W = 150 or W = 250. This implies the other dimension is 250 or 150 (order doesn't matter since we can choose a different L. The dimensions are basically 150x250). </SPAN>\n" );
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