document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=775877>Question 775877</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The time for the bus trip between 2 towns is 45 minutes shorter than the time for a train trip. If they are 350 km apart and the train speed is 15 km/h slower than the bus, find the speed of the bus in km/h. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #473226 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=473226\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let bus speed =x\r<BR>\n" );
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document.write( "bus time = 350/x\r<BR>\n" );
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document.write( "Train speed = x-15 km/h\r<BR>\n" );
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document.write( "train time= 350/(x-15)\r<BR>\n" );
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document.write( "Train takes longer\r<BR>\n" );
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document.write( "Train time - bus time = 3/4 hour\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=350%2F%28x-15%29-350%2Fx+=3%2F4 ALIGN=MIDDLE  ALT=\"350%2F%28x-15%29-350%2Fx+=3%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "multiply the equation by 4x(x-15)\r<BR>\n" );
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document.write( "4x*350-4*350(x-15)=3x(x-15)\r<BR>\n" );
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document.write( "1400x-1400x+21000=3x^2-45x\r<BR>\n" );
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document.write( "Rearrange<BR>\n" );
document.write( "3x^2-45x-21000=0\r<BR>\n" );
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document.write( "/3<BR>\n" );
document.write( "x^2-15x-7000=0\r<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=	1	,	b=	-15	,	c=	-7000<BR>\n" );
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document.write( "b^2-4ac=	225	+	28000				<BR>\n" );
document.write( "b^2-4ac=	28225						<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%09sqrt%28%0928225%09%29=%09168%09 ALIGN=MIDDLE  ALT=\"%09sqrt%28%0928225%09%29=%09168%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=(	15	+	168	)/	2		<BR>\n" );
document.write( "x1=	91.50						<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=(	15	-168	) /	2			<BR>\n" );
document.write( "x2=	-76.50						<BR>\n" );
document.write( "Ignore negative value							<BR>\n" );
document.write( "bus   	speed	91.50	km/h				\r<BR>\n" );
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document.write( " </SPAN>\n" );
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