document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=925376>Question 925376</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat moves 12 mph in still water. it travels 45 mi upstream and 45 mi downstream in a total time of 8.0 hrs. what is the speed if the current? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #561478 by </B><A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><B>TimothyLamb(4379)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><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/cgi-bin/show-face.mpl?user=TimothyLamb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=561478\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x = speed of current<BR>\n" );
document.write( "s = d/t<BR>\n" );
document.write( "---<BR>\n" );
document.write( "up:<BR>\n" );
document.write( "12 + x = 45/tu<BR>\n" );
document.write( "tu = 45/(12 + x)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "down:<BR>\n" );
document.write( "12 - x = 45/td<BR>\n" );
document.write( "td = 45/(12 - x)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "tu + td = 8 = 45/(12 + x) + 45/(12 - x)<BR>\n" );
document.write( "8 = 45(12 - x)/(12 - x)(12 + x) + 45(12 + x)/(12 - x)(12 + x)<BR>\n" );
document.write( "8 = ( 45(12 - x) + 45(12 + x) )/(12 - x)(12 + x)<BR>\n" );
document.write( "8 = ( 540 - 45x + 540 + 45x )/(144 - xx)<BR>\n" );
document.write( "8 = 1080/(144 - xx)<BR>\n" );
document.write( "8(144 - xx) = 1080<BR>\n" );
document.write( "1152 - 8xx = 1080<BR>\n" );
document.write( "8xx = 1152 - 1080<BR>\n" );
document.write( "xx = (1152 - 1080)/8<BR>\n" );
document.write( "xx = 9<BR>\n" );
document.write( "x = 3<BR>\n" );
document.write( "---<BR>\n" );
document.write( "answer: <BR>\n" );
document.write( "x = speed of current = 3 mph<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Solve and graph linear equations:<BR>\n" );
document.write( "https://sooeet.com/math/linear-equation-solver.php<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Solve quadratic equations, quadratic formula:<BR>\n" );
document.write( "https://sooeet.com/math/quadratic-formula-solver.php<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Convert fractions, decimals, and percents:<BR>\n" );
document.write( "https://sooeet.com/math/fraction-decimal-percent.php<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Calculate and graph the linear regression of any data set:<BR>\n" );
document.write( "https://sooeet.com/math/linear-regression.php </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );