document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=966615>Question 966615</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat travels 40 kilometers upriver and then returns to its starting place. If the entire trip takes 1 hour and 48 minutes and the speed of the current is 5 kilometers per hour, find the speed of the boat 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 #590770 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=590770\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> RT=D basic rule\r<BR>\n" );
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document.write( "___________________rate___________time___________distance<BR>\n" );
document.write( "UUPP_______________r-c____________u______________d<BR>\n" );
document.write( "DOWN_______________r+c____________b______________d<BR>\n" );
document.write( "Total_____________________________t\r<BR>\n" );
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document.write( "r,u,b, are unknown.\r<BR>\n" );
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document.write( "c=5<BR>\n" );
document.write( "t=1+4/5<BR>\n" );
document.write( "d=40\r<BR>\n" );
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document.write( "Make the system of three equations.\r<BR>\n" );
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document.write( "You might make the system smaller near the start if you first use the time sum equation:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%2Bu=t ALIGN=MIDDLE  ALT=\"b%2Bu=t\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and then<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=u=t-b ALIGN=MIDDLE  ALT=\"u=t-b\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you then will have this system:\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%29%28t-b%29=d%2C%28r%2Bc%29b=d%29 ALIGN=MIDDLE  ALT=\"system%28%28r-c%29%28t-b%29=d%2C%28r%2Bc%29b=d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >;<BR>\n" );
document.write( "and the unknown variables are r and b. </SPAN>\n" );
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