document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=726623>Question 726623</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The current of a stream moves at a speed of 5km/hr. A boat travels 31 km upstream back in 11 hours. What is the speed of the boat in still water?  Round your answer to two decimal places.\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 #444691 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=444691\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I presume 31 km is up and down each way\r<BR>\n" );
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document.write( "boat   	speed	x   	kph														<BR>\n" );
document.write( "current     	speed	5	kph														<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "against	current     	x-	5	kph													<BR>\n" );
document.write( "with	current     	x+	5	kph													<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "Distance=	31	miles															<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "Time against + time with  =			11	hours													<BR>\n" );
document.write( "t=d/r																	<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "31	/(	x   	+	5	)	+	31	/(x	-	5	)	=	11				<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "LCD =	(x	-	5	)	(	x   	+	5	)								<BR>\n" );
document.write( "31	*(	x   	-	5	)	+	31	(x	+	5	)	=	11	(x^2	-	25	)<BR>\n" );
document.write( "31	x   	-	-155	+	31	x   	+	155		=	11	(	x ^2		-	25	)<BR>\n" );
document.write( "62	x   	=	11	x ^2		-275											<BR>\n" );
document.write( "11	x ^2	-	-62	x   	-	275											<BR>\n" );
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document.write( "Find the roots of the equation by quadratic formula																	<BR>\n" );
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document.write( "a=	11	,	b=	-62	,	c=	-275										<BR>\n" );
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document.write( "b^2-4ac=	3844	+	12100														<BR>\n" );
document.write( "b^2-4ac=	15944																<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%09sqrt%28%0915944%09%29=%09126.27%09 ALIGN=MIDDLE  ALT=\"%09sqrt%28%0915944%09%29=%09126.27%09\"   DISABLED_style= \"max-width:90%; height:auto;\" >												<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >																	0<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >																	<BR>\n" );
document.write( "x1=(	62	+	126.27	)/	22												<BR>\n" );
document.write( "x1=	8.56																<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >																	<BR>\n" );
document.write( "x2=(	62	-126.27	) /	22													<BR>\n" );
document.write( "x2=	-2.92																<BR>\n" );
document.write( "Ignore negative value																	<BR>\n" );
document.write( "boat   	speed	8.56	kph														<BR>\n" );
document.write( "																	<BR>\n" );
document.write( "m.ananth@hotmail.ca																	<BR>\n" );
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