document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=865689>Question 865689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello, I am having a hard time knowing how to set-up and solve this word problem:\r<BR>\n" );
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document.write( "The Connecticut River flows at a rate of 4km/h for the length of a popular scenic route.  In order for a cruiser to travel 60 km upriver and then return in a total of 8hr, how fast must the boat be able to travel in still water?\r<BR>\n" );
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document.write( "Thanks for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #521811 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=521811\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The Connecticut River flows at a rate of 4km/h for the length of a popular scenic route. In order for a cruiser to travel 60 km upriver and then return in a total of 8hr, how fast must the boat be able to travel in still water?<BR>\n" );
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document.write( "let x=speed of boat in still water<BR>\n" );
document.write( "x+4=speed of boat down river<BR>\n" );
document.write( "x-4=speed of boat up river<BR>\n" );
document.write( "travel time=distance/speed<BR>\n" );
document.write( "..<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=60%2F%28x-4%29%2B60%2F%28x%2B4%29=8 ALIGN=MIDDLE  ALT=\"60%2F%28x-4%29%2B60%2F%28x%2B4%29=8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "LCD:(x-4)(x+4)<BR>\n" );
document.write( "60(x+4)+60(x-4)=8(x+4)(x-4)<BR>\n" );
document.write( "60x+240+60x-240=8(x^2-16)<BR>\n" );
document.write( "120x=8x^2-128<BR>\n" );
document.write( "8x^2-120x-128=0<BR>\n" );
document.write( "x^2-15-16<BR>\n" );
document.write( "(x-16)(x+1)=0<BR>\n" );
document.write( "x=-1 (reject, x>0)<BR>\n" );
document.write( "or <BR>\n" );
document.write( "x=16<BR>\n" );
document.write( "how fast must the boat be able to travel in still water? 16 km/h </SPAN>\n" );
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