document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136979>Question 136979</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help...<BR>\n" );
document.write( "A boat moves 7 kph in still water. It travels 445 km upriver and 45 km downriver in a total time of 14 hours. What is the speed of the current?<BR>\n" );
document.write( "All I know is that the distances are equal.<BR>\n" );
document.write( "But I don't know how to set up the equation and how to solve it.<BR>\n" );
document.write( "Thank you for the help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100249 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=100249\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=rt or d/r=t<BR>\n" );
document.write( "45/(7+x)+4/(7-x)=14<BR>\n" );
document.write( "[45(7-x)+45(7+x)]/(7+x)(7-x)=14<BR>\n" );
document.write( "[315-45x+315+45x]/(49-x^2)=14<BR>\n" );
document.write( "630/(49-x^2)=14 now cross multiply<BR>\n" );
document.write( "14(49-x^2)=630<BR>\n" );
document.write( "686-14x^2=630<BR>\n" );
document.write( "-14x^2=630-686<BR>\n" );
document.write( "-14x^2=-56<BR>\n" );
document.write( "x^2=-56/-14<BR>\n" );
document.write( "x^2=4 <BR>\n" );
document.write( "x=sqrt4<BR>\n" );
document.write( "x=2 kmph is the speed of the current.<BR>\n" );
document.write( "45/(7+2)+45/(7-2)=14<BR>\n" );
document.write( "45/9+45/5=14<BR>\n" );
document.write( "5+9=14<BR>\n" );
document.write( "14=14\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );