document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1046197>Question 1046197</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It took a crew 3 h 45 min to row 9 km upstream and back again. If the rate of flow of the stream was 1 km/h, what was the rowing speed of the crew in still water?\r<BR>\n" );
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document.write( "I got to 5x^2-24x-5=0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #661681 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel555><B>jorel555(1290)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel555><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=661681\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x be the rowing speed of the crew. Then:<BR>\n" );
document.write( "9/(x+1)+9/(x-1)=3.75<BR>\n" );
document.write( "9(x-1)+9(x+1)=3.75x²-3.75<BR>\n" );
document.write( "36x-36+36x+36=15x²-15<BR>\n" );
document.write( "15x²-72x-15=0<BR>\n" );
document.write( "(15x+3)(x-5)=0<BR>\n" );
document.write( "x=-3/15,5<BR>\n" );
document.write( "Throwing out the negative result, the rowing speed of the crew in still water was 5 kph. &#9786;&#9786;&#9786;&#9786;<BR>\n" );
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