document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=165221>Question 165221</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help with this.<BR>\n" );
document.write( "Judy averaged 42 miles per hour(mph) driving from Allentown to Harrisburg and 51 mph driving from Harrisburg to Pittsburg.  If she drove a total of 288 miles in 6 hours, then how long did it take her to drive from Harrisburg to Pittsburg?\r<BR>\n" );
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document.write( "I set this up a 2 equations using a chart as:   Distance     Speed      Time\r<BR>\n" );
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document.write( "                        Allentown to Harrisburg     x          42        42x\r<BR>\n" );
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document.write( "                        Harrisburg to Pittsburg     y          51        51y\r<BR>\n" );
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document.write( "                        Allentown to Pittsburg     288     288/6=48       6\r<BR>\n" );
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document.write( "Now         x + y = 288\r<BR>\n" );
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document.write( "          42x + 51y = 6  by substitition using y = 288 - x<BR>\n" );
document.write( "        <BR>\n" );
document.write( "          42x + 51(288-x) = 6<BR>\n" );
document.write( "       42x + 14,688 -51x  = 6<BR>\n" );
document.write( "                  -9x = -14,682 and  x = 1631.33\r<BR>\n" );
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document.write( "It works out when you plug back in, but can't be true since there is a total of only 288 miles.   The y then is a negative number which satisfies the equation.  Pleas help.  Thanks Claudia\r<BR>\n" );
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document.write( "TheISBN shows:   ISBN-13: 978-0-07-326862-0<BR>\n" );
document.write( "                  ISBN-10: 0-07-326862-3\r<BR>\n" );
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document.write( "                  Part of\r<BR>\n" );
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document.write( "                  ISBN-13: 978-0-07-326938-2<BR>\n" );
document.write( "                  ISBN-10: 0-07-326938-7 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #121780 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=121780\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> rt=d __ you have the rates, the total time and the total distance\r<BR>\n" );
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document.write( "let x=\"time from Harrisburg to Pittsburg\", so 6-x=\"time from Allentown to Harrisburg\"\r<BR>\n" );
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document.write( "51(x)+42(6-x)=288 __ 51x+252-42x=288 __ 9x=36 __ x=4 </SPAN>\n" );
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