document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=862027>Question 862027</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two boats travel on a river between two towns and have the same two constant speeds: a high speed downstream and a low speed upstream. Boat 1 leaves town A as boat 2 leaves town B. They pass each other 7 miles from town A, stop 4 minutes at their destinations, and pass again 9 miles from town A. What is the distance between the towns? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #519594 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=519594\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Two boats travel on a river between two towns and have the same two constant speeds:<BR>\n" );
document.write( "a high speed downstream and a low speed upstream.<BR>\n" );
document.write( "Boat 1 leaves town A as boat 2 leaves town B.<BR>\n" );
document.write( "They pass each other 7 miles from town A, stop 4 minutes at their destinations, and pass again 9 miles from town A.<BR>\n" );
document.write( "What is the distance between the towns?<BR>\n" );
document.write( ":<BR>\n" );
document.write( "let d = distance between A & B<BR>\n" );
document.write( ":<BR>\n" );
document.write( "At first meeting<BR>\n" );
document.write( "Boat 1 travels 7 mi<BR>\n" );
document.write( "Boat 2 travels (d-7)<BR>\n" );
document.write( "At 2nd meeting<BR>\n" );
document.write( "Boat 1 travels: (d-7)+(d-9) = 2d-16<BR>\n" );
document.write( "Boat 2 travels: 7 + 9 = 16 mi<BR>\n" );
document.write( "let x = the upstream speed<BR>\n" );
document.write( "let y = the downstream speed<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation, time = dist/speed<BR>\n" );
document.write( "First meeting<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2Fx ALIGN=MIDDLE  ALT=\"7%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28d-7%29%29%2Fy ALIGN=MIDDLE  ALT=\"%28%28d-7%29%29%2Fy\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "7y = x(d-7)<BR>\n" );
document.write( "2nd meeting<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28d-7%29%29%2Fx ALIGN=MIDDLE  ALT=\"%28%28d-7%29%29%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28d-9%29%29%2Fy ALIGN=MIDDLE  ALT=\"%28%28d-9%29%29%2Fy\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2Fy ALIGN=MIDDLE  ALT=\"7%2Fy\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2Fx ALIGN=MIDDLE  ALT=\"9%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "mult by xy<BR>\n" );
document.write( "y(d-7) + x(d-9) = 7x + 9y<BR>\n" );
document.write( "dy - 7y + dx - 9x = 7x + 9y<BR>\n" );
document.write( "dy + dx = 7x + 9x + 9y + 7y<BR>\n" );
document.write( "d(x+y) = 16x + 16y<BR>\n" );
document.write( "d(x+y) = 16(x+y)<BR>\n" );
document.write( "divide both sides by (x+y)<BR>\n" );
document.write( "d = 16 mi distance from A to B\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
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