document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=507816>Question 507816</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A driver averaged a speed of 20 kph more on a trip from A to B than on the return trip.  The return trip took one and a half times as long.  What was the average speed of the trip from a) point A to point B  and b) point B to point A? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #340756 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=340756\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Always start with d=rt, the fundamental distance equation.<BR>\n" );
document.write( "In this case, d = d because the driver goes from A to B and then from B to A.<BR>\n" );
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document.write( "A-to-B trip:<BR>\n" );
document.write( "r = x<BR>\n" );
document.write( "t = y<BR>\n" );
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document.write( "B-to-A trip:<BR>\n" );
document.write( "r = x-20<BR>\n" );
document.write( "t = 3/2*y<BR>\n" );
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document.write( "d=d<BR>\n" );
document.write( "so<BR>\n" );
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document.write( "x*y = (x-20)*(3/2*y)<BR>\n" );
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document.write( "multiply both sides by 2 to eliminate fraction<BR>\n" );
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document.write( "2xy =(x-20)(3y)<BR>\n" );
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document.write( "2xy = 3xy -60y<BR>\n" );
document.write( "xy -60y = 0<BR>\n" );
document.write( "y(x-60) = 0<BR>\n" );
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document.write( "x = 60<BR>\n" );
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document.write( "Recall 'x' is the average speed going from A to B.<BR>\n" );
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document.write( "So, x-20 = 40 is the average speed going from B to A.<BR>\n" );
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document.write( "Note that we do not know 't' or 'd', but we have answered the question about 'r'.<BR>\n" );
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document.write( "Done. </SPAN>\n" );
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