document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=828691>Question 828691</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Liz and Mary took a canoeing trip, traveling 6 miles upstream along a river, against a 2 mph current. They returned downstream to the starting point of their trip. If the entire trip took 4 hours, what was their rate in still water ?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #499471 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=499471\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d = 6<BR>\n" );
document.write( "r = canoe speed without current<BR>\n" );
document.write( "c = 2, speed of current<BR>\n" );
document.write( "T =4, total time\r<BR>\n" );
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document.write( "______________speed_____________time______________distance<BR>\n" );
document.write( "Going_________r-2_______________(___)_____________6<BR>\n" );
document.write( "Return________r+2_______________(___)_____________6<BR>\n" );
document.write( "Total____________________________T\r<BR>\n" );
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document.write( "What are the missing time parts?\r<BR>\n" );
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document.write( "______________speed_____________time______________distance<BR>\n" );
document.write( "Going_________r-2_______________(6/(r-2))_____________6<BR>\n" );
document.write( "Return________r+2_______________(6/(r+2))_____________6<BR>\n" );
document.write( "Total____________________________T\r<BR>\n" );
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document.write( "Obvious equation is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F%28r-2%29%2B6%2F%28r%2B2%29=T ALIGN=MIDDLE  ALT=\"6%2F%28r-2%29%2B6%2F%28r%2B2%29=T\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%281%2F%28r-2%29%2B1%2F%28r-2%29%29=T ALIGN=MIDDLE  ALT=\"6%281%2F%28r-2%29%2B1%2F%28r-2%29%29=T\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%28%28r%2B2%2Br-2%29%2F%28r%5E2-4%29%29=T ALIGN=MIDDLE  ALT=\"6%28%28r%2B2%2Br-2%29%2F%28r%5E2-4%29%29=T\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%282r%29%2F%28r%5E2-4%29=T ALIGN=MIDDLE  ALT=\"6%282r%29%2F%28r%5E2-4%29=T\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%2F%28r%5E2-4%29=T%2F12 ALIGN=MIDDLE  ALT=\"r%2F%28r%5E2-4%29=T%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=%28r%5E2-4%29T%2F12 ALIGN=MIDDLE  ALT=\"r=%28r%5E2-4%29T%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" >  and we already know T=4<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=%28r%5E2-4%29%284%2F12%29 ALIGN=MIDDLE  ALT=\"r=%28r%5E2-4%29%284%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=%281%2F3%29%28r%5E2-4%29 ALIGN=MIDDLE  ALT=\"r=%281%2F3%29%28r%5E2-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3r=r%5E2-4 ALIGN=MIDDLE  ALT=\"3r=r%5E2-4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28r%5E2-3r-4=0%29 ALIGN=MIDDLE  ALT=\"highlight_green%28r%5E2-3r-4=0%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  ------ seems factorable.  One solution will make sense and the other will not make sense.\r<BR>\n" );
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document.write( "(r-4)(r+1)=0 </SPAN>\n" );
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