document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=4796>Question 4796</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the problem:\r<BR>\n" );
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document.write( "The printed matter on a 12 by 18 centimeter page of a book must cover 40 square centimeters.  If all margins are to be the same width, how wide should the margins be? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #2327 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=2327\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It's often helpful to draw yourself a diagram that graphically depicts the situation to be solved.\r<BR>\n" );
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document.write( "I don't know how to draw diagrams with this system but you can readily see that your picture would show a smaller rectangle centered inside of a larger rectangle. The smaller rectangle represents the area (40 cm^2) covered by the printed matter while the larger rectangle represents the page whose dimensions are 12 cm X 18 cm.\r<BR>\n" );
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document.write( "Let the width of the uniform margin be x cm.\r<BR>\n" );
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document.write( "Now you can set up your equation for finding x:\r<BR>\n" );
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document.write( "We'll need to write the equation for the area of the smaller rectangle in terms of x, the width of the margin.\r<BR>\n" );
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document.write( "The width othe smaller rectangle can be written:  W = 12-2x and the length can be written: L = 18-2x\r<BR>\n" );
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document.write( "The area. A = L*W = (18-2x)(12-2x) = 40 cm^2\r<BR>\n" );
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document.write( "So as not to take all the fun out of this for you, I'll let you work this out yourself: \r<BR>\n" );
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document.write( "(18-2x)(12-2x) = 40 \r<BR>\n" );
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document.write( "Hint: You will get a quadratic equation that looks like this: 4x^2-60x+176 = 0\r<BR>\n" );
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document.write( "You need to solve this for x and when you do, you will find that there are two values of x (no surprise here since solutions to quadratic equations yield two roots).\r<BR>\n" );
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document.write( "What needs to be determined is...which value of x is the solution to the problem?  Both values are positive!  But only one of the values makes any physical sense in this problem. \r<BR>\n" );
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document.write( "Try this.  If you run into insurmountable difficulties, post another question.<BR>\n" );
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