document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1050063>Question 1050063</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 3 mile boat race takes place in Detroit every year. The current in the river is 4 mph. What is the speed od the boat in still water if the total time of upstream and downstream is 1 hour </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #665673 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=665673\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = time spent going downstream<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1+-+t+ ALIGN=MIDDLE  ALT=\"+1+-+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = time spent going upstream<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+ ALIGN=MIDDLE  ALT=\"+s+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the speed of the boat in still water<BR>\n" );
document.write( "------------------------------------------<BR>\n" );
document.write( "Equation for going downstream:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+%28+s+%2B+4+%29%2At+ ALIGN=MIDDLE  ALT=\"+1.5+=+%28+s+%2B+4+%29%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation for going upstream:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+%28+s+-+4+%29%2A%28+1+-+t+%29+ ALIGN=MIDDLE  ALT=\"+1.5+=+%28+s+-+4+%29%2A%28+1+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+s+-+4+-+s%2At+%2B+4t+ ALIGN=MIDDLE  ALT=\"+1.5+=+s+-+4+-+s%2At+%2B+4t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+s+-+4+%2B+t%2A%28+4+-+s+%29+ ALIGN=MIDDLE  ALT=\"+1.5+=+s+-+4+%2B+t%2A%28+4+-+s+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+1.5+%2F+%28+s+%2B+4+%29+ ALIGN=MIDDLE  ALT=\"+t+=+1.5+%2F+%28+s+%2B+4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute (1) into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+s+-+4+%2B+%28+1.5+%2F+%28+s%2B4+%29+%29%2A%28+4+-+s+%29+ ALIGN=MIDDLE  ALT=\"+1.5+=+s+-+4+%2B+%28+1.5+%2F+%28+s%2B4+%29+%29%2A%28+4+-+s+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5.5+=+s+%2B+%28+1.5+%2F+%28+s%2B4+%29+%29%2A%28+4+-+s+%29+ ALIGN=MIDDLE  ALT=\"+5.5+=+s+%2B+%28+1.5+%2F+%28+s%2B4+%29+%29%2A%28+4+-+s+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%2B4+ ALIGN=MIDDLE  ALT=\"+s%2B4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5.5%2A%28+s%2B4+%29+=+s%2A%28+s%2B4+%29+%2B+1.5%2A%28+4+-+s+%29+ ALIGN=MIDDLE  ALT=\"+5.5%2A%28+s%2B4+%29+=+s%2A%28+s%2B4+%29+%2B+1.5%2A%28+4+-+s+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5.5s+%2B+22+=+s%5E2+%2B+4s+%2B+6+-+1.5s+ ALIGN=MIDDLE  ALT=\"+5.5s+%2B+22+=+s%5E2+%2B+4s+%2B+6+-+1.5s+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+%2B+2.5s+%2B+6+=+5.5s+%2B+22+ ALIGN=MIDDLE  ALT=\"+s%5E2+%2B+2.5s+%2B+6+=+5.5s+%2B+22+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+3s+=+16+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+3s+=+16+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "I'll try completing the square:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+3s+%2B+%28+-3%2F2%29%5E2+=+16+%2B+%28-3%2F2%29%5E2+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+3s+%2B+%28+-3%2F2%29%5E2+=+16+%2B+%28-3%2F2%29%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+3s+%2B+9%2F4+=+16+%2B+9%2F4+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+3s+%2B+9%2F4+=+16+%2B+9%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+3s+%2B+9%2F4+=+64%2F4+%2B+9%2F4+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+3s+%2B+9%2F4+=+64%2F4+%2B+9%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+3s+%2B+9%2F4+=+73%2F4+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+3s+%2B+9%2F4+=+73%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+s+-+3%2F2+%29%5E2+=+73%2F4+ ALIGN=MIDDLE  ALT=\"+%28+s+-+3%2F2+%29%5E2+=+73%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+-+3%2F2+=+%281%2F2%29%2Asqrt%2873%29+ ALIGN=MIDDLE  ALT=\"+s+-+3%2F2+=+%281%2F2%29%2Asqrt%2873%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+%281%2F2%29%2A8.544+%2B+3%2F2+ ALIGN=MIDDLE  ALT=\"+s+=+%281%2F2%29%2A8.544+%2B+3%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+4.272+%2B+1.5+ ALIGN=MIDDLE  ALT=\"+s+=+4.272+%2B+1.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+5.772+ ALIGN=MIDDLE  ALT=\"+s+=+5.772+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "----------------------------<BR>\n" );
document.write( "check answer:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+1.5+%2F+%28+s+%2B+4+%29+ ALIGN=MIDDLE  ALT=\"+t+=+1.5+%2F+%28+s+%2B+4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+1.5+%2F+%28+5.772+%2B+4+%29+ ALIGN=MIDDLE  ALT=\"+t+=+1.5+%2F+%28+5.772+%2B+4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+1.5%2F9.772+ ALIGN=MIDDLE  ALT=\"+t+=+1.5%2F9.772+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+.1535+ ALIGN=MIDDLE  ALT=\"+t+=+.1535+\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+%28+5.772+-+4+%29%2A%28+1+-+t+%29+ ALIGN=MIDDLE  ALT=\"+1.5+=+%28+5.772+-+4+%29%2A%28+1+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+1.772%2A%28+1+-+t+%29+ ALIGN=MIDDLE  ALT=\"+1.5+=+1.772%2A%28+1+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.5+=+1.772+-+1.772t+ ALIGN=MIDDLE  ALT=\"+1.5+=+1.772+-+1.772t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.772t+=+.272+ ALIGN=MIDDLE  ALT=\"+1.772t+=+.272+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+.1535+ ALIGN=MIDDLE  ALT=\"+t+=+.1535+\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "It's about a 9 minute race! ( if I'm right )\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );