document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=161270>Question 161270</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Cathy traveled by boat 4 miles upstream to fish. Because of the 5mph current it took her 40 minutes longer to get there than to return. How fast will her boat go 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 #118792 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=118792\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Cathy traveled by boat 4 miles upstream to fish. Because of the 5mph current it took her 40 minutes longer to get there than to return. How fast will her boat go in still water?<BR>\n" );
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document.write( "Let s = speed in still water<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+5) = speed downstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(x-5) = speed upstream<BR>\n" );
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document.write( "Change 40 min to hrs: 40 min = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > hr<BR>\n" );
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document.write( "Write time equation; time = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dist%2Fspeed ALIGN=MIDDLE  ALT=\"dist%2Fspeed\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Downstream time + 2/3 hr = upstream time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F%28%28s%2B5%29%29 ALIGN=MIDDLE  ALT=\"4%2F%28%28s%2B5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F%28%28s-5%29%29 ALIGN=MIDDLE  ALT=\"4%2F%28%28s-5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Multiply equation by 3(s-5)(s+5) to get rid of the denominators<BR>\n" );
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document.write( "4(3(s-5)) + 2(s-5)(s+5) = 4(3(s+5))<BR>\n" );
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document.write( "12s - 60 + 2(s^2 - 25) = 12s + 60<BR>\n" );
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document.write( "12s - 60 + 2s^2 - 50 = 12s + 60<BR>\n" );
document.write( "Combine like terms on the left<BR>\n" );
document.write( "2s^2 + 12s - 12s - 60 - 50 - 60 = 0<BR>\n" );
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document.write( "2s^2 - 170 = 0<BR>\n" );
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document.write( "2s^2 = +170<BR>\n" );
document.write( "s^2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=170%2F2 ALIGN=MIDDLE  ALT=\"170%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s^2 = 85<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2885%29 ALIGN=MIDDLE  ALT=\"sqrt%2885%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 9.22 mph in still water<BR>\n" );
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document.write( "Check solution on a calc:<BR>\n" );
document.write( "4/14.22 + .67 = .95<BR>\n" );
document.write( "4/4.22 = .95 </SPAN>\n" );
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