document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=993575>Question 993575</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Jina drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took <BR>\n" );
document.write( "12<BR>\n" );
document.write( " hours. When Jina drove home, there was no traffic and the trip only took <BR>\n" );
document.write( "8<BR>\n" );
document.write( " hours. If her average rate was <BR>\n" );
document.write( "20<BR>\n" );
document.write( " miles per hour faster on the trip home, how far away does Jina live from the mountains? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #612882 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=612882\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> rate * time = distance.\r<BR>\n" );
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document.write( "let r = rate going to the mountains.<BR>\n" );
document.write( "let r + 20 = rate coming back from the mountains.\r<BR>\n" );
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document.write( "going time = 12 hours, so rate * time = distance becomes:\r<BR>\n" );
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document.write( "rate * 12 = distance\r<BR>\n" );
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document.write( "coming back time = 8 hours, so rate * time = distance becomes:\r<BR>\n" );
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document.write( "(rate + 20) * 8 = distance.\r<BR>\n" );
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document.write( "let r = rate and d = distance and your formulas become:\r<BR>\n" );
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document.write( "r * 12 = d<BR>\n" );
document.write( "(r + 20) * 8 = d\r<BR>\n" );
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document.write( "simplify the second equation to get:\r<BR>\n" );
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document.write( "r * 8 + 20 * 8 = d\r<BR>\n" );
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document.write( "simplify it further to get:\r<BR>\n" );
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document.write( "r * 8 + 160 = d\r<BR>\n" );
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document.write( "your two equations are now:\r<BR>\n" );
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document.write( "r * 12 = d<BR>\n" );
document.write( "r * 8 + 160 = d\r<BR>\n" );
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document.write( "subtract the second equation from the first equation and you get:\r<BR>\n" );
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document.write( "r * 4 - 160 = 0\r<BR>\n" );
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document.write( "add 160 to both sides of the equation to get:\r<BR>\n" );
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document.write( "r * 4 = 160\r<BR>\n" );
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document.write( "divide both sides of the equation by 4 to get:\r<BR>\n" );
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document.write( "r = 40\r<BR>\n" );
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document.write( "if r = 40, then r + 20 = 60\r<BR>\n" );
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document.write( "she traveled at 40 miles per hour going and 60 miles per hour coming back.\r<BR>\n" );
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document.write( "12 * 40 = 480\r<BR>\n" );
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document.write( "8 * 60 = 480\r<BR>\n" );
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document.write( "distance is 480 miles.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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