document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=868804>Question 868804</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write a system of two equations in two variables to solve the problem.\r<BR>\n" );
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document.write( "Flying with a tailwind, a pilot flew an airplane 720 miles in 4.5 hours. Flying into a headwind, the return trip took 6 hours. Find the speed of the plane in calm air and the speed of the wind. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #523835 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=523835\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Plane	speed	=x	mph					<BR>\n" );
document.write( "wind  	speed	=y	mph					<BR>\n" );
document.write( "against  	wind  	6	hours					<BR>\n" );
document.write( "with	wind  	4.5	hours					<BR>\n" );
document.write( "								<BR>\n" );
document.write( "Distance against 		720	miles	distance with 		720	miles	<BR>\n" );
document.write( "t=d/r	against	wind  		-				<BR>\n" );
document.write( "720.00	/	(	x	-	y	)=	6.00	<BR>\n" );
document.write( "6.00	(	x	-	y	)	=	4.50	<BR>\n" );
document.write( "6.00	x	-	6.00	y	=	720.00	....................1	<BR>\n" );
document.write( "								<BR>\n" );
document.write( "720.00	/	(	x	+	y	)=	4.50	<BR>\n" );
document.write( "4.50	(	x	+	y	)	=	720.00	<BR>\n" );
document.write( "4.50	x	+	4.50	y	=	720.00	...............2	<BR>\n" );
document.write( "Multiply (1) by	4.50							<BR>\n" );
document.write( "Multiply (2) by	6.00							<BR>\n" );
document.write( "we get								<BR>\n" );
document.write( "27.00	x	+	-27.00	y	=	3240.00		<BR>\n" );
document.write( "27.00	x	+	27.00	y	=	4320.00		<BR>\n" );
document.write( "54.00	x	=	7560.00					<BR>\n" );
document.write( "/	54.00							<BR>\n" );
document.write( "x	=	140.00	mph					<BR>\n" );
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document.write( "plug value of x in (1)				y				<BR>\n" );
document.write( "6.00	x		-6.00	y	=	720.00		<BR>\n" );
document.write( "840.00			-6.00	-840.00	=	720.00		<BR>\n" );
document.write( "-6.00	y	=	720.00					<BR>\n" );
document.write( "-6.00	y	=	-120.00	mph				<BR>\n" );
document.write( "	y	=	20.00					<BR>\n" );
document.write( "Plane	speed	140.00	mph					<BR>\n" );
document.write( "wind  	speed	20.00	mph					<BR>\n" );
document.write( "								<BR>\n" );
document.write( "m.ananth@hotmail.ca								     <BR>\n" );
document.write( " </SPAN>\n" );
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