document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=830597>Question 830597</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a boat travels from Town A to Town B, it has to travel 1501.5 mi along a river.\r<BR>\n" );
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document.write( "A boat traveled from Town A to Town B along the river’s current with its engine running at full speed. This trip took 71.5 hr.\r<BR>\n" );
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document.write( "Then the boat traveled back from Town B to Town A, again with the engine at full speed, but this time against the river’s current. This trip took 136.5 hr.\r<BR>\n" );
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document.write( "Write and solve a system of equations to answer the following questions.\r<BR>\n" );
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document.write( "The boat’s speed in still water with the engine running at full speed is?\r<BR>\n" );
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document.write( "The river current’s speed was?\r<BR>\n" );
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document.write( "I tried D/T=R for each. Then I'm stumped from there. I'm really unsure of how to set up this equation. If I could have some help as to how to set it up, I know I can solve it. Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #500717 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=500717\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  If a boat travels from Town A to Town B, it has to travel 1501.5 mi along a river.<BR>\n" );
document.write( "A boat traveled from Town A to Town B along the river’s current with its engine running at full speed. This trip took 71.5 hr.<BR>\n" );
document.write( "Then the boat traveled back from Town B to Town A, again with the engine at full speed, but this time against the river’s current. This trip took 136.5 hr. <BR>\n" );
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document.write( "Let s = boat speed in still water<BR>\n" );
document.write( "Let c = rate of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+c) = effective speed downstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s-c) = effective speed upstream\<BR>\n" );
document.write( "Write and solve a system of equations<BR>\n" );
document.write( "write a distance equation for each way; dist = time * speed<BR>\n" );
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document.write( "71.5(s + c) = 1501.5<BR>\n" );
document.write( "136.5(s - c) = 1501.5<BR>\n" );
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document.write( "They make it easy for you, simplify, divide the 1st equation by 71.5<BR>\n" );
document.write( "Divide the 2nd equation by 136.5, leaving an easy elimination problem<BR>\n" );
document.write( "s + c = 21<BR>\n" );
document.write( "s - c = 11<BR>\n" );
document.write( "--------------adding eliminates c, find s<BR>\n" );
document.write( "2s = 32<BR>\n" );
document.write( "s = 16 mph in still water<BR>\n" );
document.write( "I'll let you find the current<BR>\n" );
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