document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=600811>Question 600811</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat travels 8 km upstream and 8 km back. The time for the round trip is 2 hrs. The speed of the stream is 4 km/hr. What is the speed of the boat 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 #379502 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=379502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Boat  	speed	x   	mph													<BR>\n" );
document.write( "current     	speed	4	mph													<BR>\n" );
document.write( "																<BR>\n" );
document.write( "against	current     	x-	4	mph												<BR>\n" );
document.write( "with	current     	x+	4	mph												<BR>\n" );
document.write( "																<BR>\n" );
document.write( "Distance=	8	miles														<BR>\n" );
document.write( "																<BR>\n" );
document.write( "Time against + time with  =2	hours												<BR>\n" );
document.write( "t=d/r																<BR>\n" );
document.write( "																<BR>\n" );
document.write( "8/(x+4)	+8/(x-4)=	2			<BR>\n" );
document.write( "																<BR>\n" );
document.write( "LCD =(x-4)(x+4)							<BR>\n" );
document.write( "8*(x-4)	+8(x+4)	=2(x^2-16)<BR>\n" );
document.write( "8x-32+8x+32=2(x ^2-16)<BR>\n" );
document.write( "16	x   	=	2	x ^2		-32										<BR>\n" );
document.write( "2	x ^2	-	-16	x   	-	32	=0<BR>\n" );
document.write( "divide by 2<BR>\n" );
document.write( "x^2-8x-16=0									<BR>\n" );
document.write( "																<BR>\n" );
document.write( "Find the roots of the equation by quadratic formula																<BR>\n" );
document.write( "																<BR>\n" );
document.write( "a=	1	,	b=	-8	,	c=	-16									<BR>\n" );
document.write( "																<BR>\n" );
document.write( "b^2-4ac=	64	+	64													<BR>\n" );
document.write( "b^2-4ac=	128															<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%09sqrt%28%09128%09%29=%0911.31%09 ALIGN=MIDDLE  ALT=\"%09sqrt%28%09128%09%29=%0911.31%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;\" >							<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=(	8	+	11.31	)/	2											<BR>\n" );
document.write( "x1=	9.66															<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=(	8	-11.31	) /	2												<BR>\n" );
document.write( "x2=	-1.66															<BR>\n" );
document.write( "Ignore negative value																<BR>\n" );
document.write( "Boat  	speed	9.66	mph													<BR>\n" );
document.write( "																<BR>\n" );
document.write( "m.ananth@hotmail.ca																<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );