document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=325959>Question 325959</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A certain plane flying with the wind travels 540 mi in 2 hr. Later, flying against the same wind, the plane<BR>\n" );
document.write( "travels 690 mi in 3 hr. Find the speed of the plane in still air and the speed of the wind.\r<BR>\n" );
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document.write( "I must solve this problem using a system of equations.\r<BR>\n" );
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document.write( "I got these two equations which led to a solution, but it doesn't seem like it was done right. 2(x + y) = 540 & 3(x – y) = 690 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #233313 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=233313\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> with the wind plane travels 540 mi in 2 hr. <BR>\n" );
document.write( "flying against , the plane travels 690 mi in 3 hr. <BR>\n" );
document.write( "..\r<BR>\n" );
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document.write( "let speed of plane in still air be x mph<BR>\n" );
document.write( "& speed of wind be y mph<BR>\n" );
document.write( "..<BR>\n" );
document.write( "With wind<BR>\n" );
document.write( "Time taken = 540 / x+y= 2<BR>\n" );
document.write( "540 =2x+2y<BR>\n" );
document.write( "270=x+y........................1<BR>\n" );
document.write( "..<BR>\n" );
document.write( "Against wind <BR>\n" );
document.write( "Time taken = 690/ x-y = 3<BR>\n" );
document.write( "..<BR>\n" );
document.write( "690=3x-3y<BR>\n" );
document.write( "230=x-y........................2<BR>\n" );
document.write( "..<BR>\n" );
document.write( "Add equation 1 & 2<BR>\n" );
document.write( "x+y+x-y=270+230<BR>\n" );
document.write( "2x=500<BR>\n" );
document.write( "x=250 mph speed of plane<BR>\n" );
document.write( "..<BR>\n" );
document.write( "plug the value of x in equation 1<BR>\n" );
document.write( "270=250+y<BR>\n" );
document.write( "y= 20 mph the speed of wind<BR>\n" );
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