document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=180881>Question 180881</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The Hudson River flows at a rate of 5 miles per hour.  A patrol boat travels 40 miles upriver, and returns in a total time of 6 hours.  What is the speed of the boat in still water?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #135618 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=135618\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The Hudson River flows at a rate of 5 miles per hour. A patrol boat travels 40 miles upriver, and returns in a total time of 6 hours. What is the speed of the boat in still water? <BR>\n" );
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document.write( "x = rate of boat<BR>\n" );
document.write( "40/(x-5) + 40/(x+5) = 6<BR>\n" );
document.write( "Time up  + time back = 6<BR>\n" );
document.write( "Multiply by (x-5)*(x+5)<BR>\n" );
document.write( "40(x+5) + 40(x-5) = 6(x+5)(x-5)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40x%2B200+%2B+40x-200+=+6x%5E2+-+150 ALIGN=MIDDLE  ALT=\"40x%2B200+%2B+40x-200+=+6x%5E2+-+150\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=80x+=+6x%5E2-150 ALIGN=MIDDLE  ALT=\"80x+=+6x%5E2-150\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%5E2+-+40x+-+75+=+0 ALIGN=MIDDLE  ALT=\"3x%5E2+-+40x+-+75+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(3x + 5)*(x - 15) = 0<BR>\n" );
document.write( "x = 15<BR>\n" );
document.write( "x = -5/3<BR>\n" );
document.write( "Ignore the negative value<BR>\n" );
document.write( "It's 15 mph\r<BR>\n" );
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