document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=559996>Question 559996</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a motorboat has a constant speed of 14 miles per hour relative to the water going upstream for 33 miles and then returning. the total trip time was 7 hours. use this information to find the speed of 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 #363769 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=363769\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a motorboat has a constant speed of 14 miles per hour relative to the water going upstream for 33 miles and then returning.<BR>\n" );
document.write( " the total trip time was 7 hours. use this information to find the speed of the current.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let c = the rate of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(14-c) = effective speed upstream (in relation to the land)<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(14+c) = effective speed downstream<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation; time = dist/speed<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Time upstr + time downstr = 7 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=33%2F%28%2814-c%29%29 ALIGN=MIDDLE  ALT=\"33%2F%28%2814-c%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=33%2F%28%2814%2Bc%29%29 ALIGN=MIDDLE  ALT=\"33%2F%28%2814%2Bc%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 7<BR>\n" );
document.write( ";<BR>\n" );
document.write( "Multiply by (14-c)(14+c), results:<BR>\n" );
document.write( "33(14+c) + 33(14-c) = 7(14-c)(14+c)<BR>\n" );
document.write( ":<BR>\n" );
document.write( "462 + 33c + 462 - 33c = 7(196-c^2)<BR>\n" );
document.write( ":<BR>\n" );
document.write( "924 = 1372 - 7c^2<BR>\n" );
document.write( ":<BR>\n" );
document.write( "7c^2 = 1372 - 924<BR>\n" );
document.write( ":<BR>\n" );
document.write( "7c^2 = 448<BR>\n" );
document.write( ":<BR>\n" );
document.write( "c^2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=448%2F7 ALIGN=MIDDLE  ALT=\"448%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c^2 = 64<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2864%29 ALIGN=MIDDLE  ALT=\"sqrt%2864%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = 8 mph is the speed of the current<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "See if this checks out. Find the actual time of each trip.<BR>\n" );
document.write( "33/(14-8) = 5.5 hrs<BR>\n" );
document.write( "33/(14+8) = 1.5 hrs<BR>\n" );
document.write( "------------------<BR>\n" );
document.write( "total time: 7.0 hrs </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );