document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=285441>Question 285441</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help with the following word problem!\r<BR>\n" );
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document.write( "A plane flies 390 mph in still air. It makes a round trip of 5040 miles in a total of 13 hours, one way with the jet stream and the other way against the jet stream. Find the speed of the jet stream.\r<BR>\n" );
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document.write( "I know that Rate X Time = Distance, so using J for jet stream and T for time, I tried (390-J) X (T) = 2520 (1/2 the distance since it was round-trip) and (390+J) X (13-T) = 2520. I also tried (390-J) X (T) = (390+J) X (13-T).\r<BR>\n" );
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document.write( "I get to a point where I'm not sure what to do with two variables. How would you set this problem up? If I am on the right track, how do I solve for 2 variables?\r<BR>\n" );
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document.write( "Thank you so much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #206918 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=206918\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2520/(390 + J) + 2520/(390-J) = 13<BR>\n" );
document.write( "2520*(390-J) + 2520*(390+J) = 13(390-J)(390+J)<BR>\n" );
document.write( "A quadratic in J<BR>\n" );
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