document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=191432>Question 191432</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat at full throttle takes two hours longer to travel 75 miles against the current than it takes to travel the same distance with current. If the rate of the current is 5 mph, then what is the speed of the boat at full throttle 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 #143670 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=143670\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A)  75=(x-5)*(t+2)                                                                      <BR>\n" );
document.write( "b)  75=(x+5)*(t)                                                 <BR>\n" );
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document.write( "a=b )          x*t+5t=x*t + 2*x - 5*t -10<BR>\n" );
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document.write( "                    5*t = -5*t + 2*x -10\r<BR>\n" );
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document.write( "                   5*t  + 5*t  = 2*x -10\r<BR>\n" );
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document.write( "                  10 *t   +10  = 2* x<BR>\n" );
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document.write( "                  5*t +5  = x\r<BR>\n" );
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document.write( "subst  in ( b )     75 =  (( 5*t+5)+(5)) *t\r<BR>\n" );
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document.write( "                          75 = ( 5*t+10) *t\r<BR>\n" );
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document.write( "                         0= 5*t^2 + 10*t - 75\r<BR>\n" );
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document.write( "                        0 = ( 5*t = 25 )  * ( t-3)\r<BR>\n" );
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document.write( "                       t= -5  Not Real       and    t= +3\r<BR>\n" );
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document.write( "subst          5*3  +5  = x\r<BR>\n" );
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document.write( "                   x = 20       ANSWER\r<BR>\n" );
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document.write( " check      75 = ( 20-5) * (3+2)  =  15 * 5  = 75     ok  \r<BR>\n" );
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document.write( "check                 75 = ( 20 + 5) * (3) = 25 * 3  =  75     ok            </SPAN>\n" );
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