document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=971783>Question 971783</A>: <I><SPAN STYLE=\"word-break: break-all;\"> assen can travel  miles downstream in his motorboat in the same time he travels 3 miles upstream. if the current of the river is 3 mph, what is the boats rate in still water? write an equation that could be used to model this problem. let r represent the boats rate (in mph) 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 #594174 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=594174\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You missed a datum in the description.  Not too bad an omission; I will generalize.\r<BR>\n" );
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document.write( "r, speed of boat for still water, UNKNOWN<BR>\n" );
document.write( "c, speed of river current<BR>\n" );
document.write( "d, distance going downstream<BR>\n" );
document.write( "u, distance going upstream<BR>\n" );
document.write( "t, time to travel either direction, UNKNOWN\r<BR>\n" );
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document.write( "___________________rate___________time__________distance<BR>\n" );
document.write( "UPSTRM_____________r-c____________t_____________u<BR>\n" );
document.write( "DOWNSTR____________r+c____________t_____________d\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28%28r-c%29t=u%2C%28r%2Bc%29t=d%29 ALIGN=MIDDLE  ALT=\"system%28%28r-c%29t=u%2C%28r%2Bc%29t=d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28t=u%2F%28r-c%29%2Ct=d%2F%28r%2Bc%29%29 ALIGN=MIDDLE  ALT=\"system%28t=u%2F%28r-c%29%2Ct=d%2F%28r%2Bc%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u%2F%28r-c%29=d%2F%28r%2Bc%29 ALIGN=MIDDLE  ALT=\"u%2F%28r-c%29=d%2F%28r%2Bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u%28r%2Bc%29=d%28r-c%29 ALIGN=MIDDLE  ALT=\"u%28r%2Bc%29=d%28r-c%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ur%2Buc=dr-dc ALIGN=MIDDLE  ALT=\"ur%2Buc=dr-dc\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ur-dr=-dc-uc ALIGN=MIDDLE  ALT=\"ur-dr=-dc-uc\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dr-ur=dc%2Buc ALIGN=MIDDLE  ALT=\"dr-ur=dc%2Buc\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which makes sense for the signs\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%28d-u%29=dc%2Buc ALIGN=MIDDLE  ALT=\"r%28d-u%29=dc%2Buc\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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