document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=258129>Question 258129</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Need your help again.  Question:  A plane flies a distance of 2900 miles.  With the tailwind, it averaged 600 mph. When the wind changed from a tailwind to a headwind, the speed dropped to 550 mph.  Total trip time is 5 hours.  Determine the length of time it flew at each speed.\r<BR>\n" );
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document.write( "My solution was:  x/600 + 2900 - x/550 = 5, which didn't work.  Thanks!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #190001 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=190001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is an RTD problem. Here is a table based on the given information:<BR>\n" );
document.write( "PLANE . . . . .rate . . . . . . . . time . . . . . . . . . distance<BR>\n" );
document.write( "with  . . . . . r+c = 600 . . . . . . Tw . . . . . . . . . . 600Tw<BR>\n" );
document.write( "against . . . . r-c = 550 . . . . . . Ta . . . . . . . . . . 550Ta<BR>\n" );
document.write( "total . . . . . . . . . . . . . . . . .5 . . . . . . . . . . 2900<BR>\n" );
document.write( "we have two equations:<BR>\n" );
document.write( "(i) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Tw+%2B+Ta+=+5 ALIGN=MIDDLE  ALT=\"Tw+%2B+Ta+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(ii) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=600Tw+%2B+550Ta+=+2900 ALIGN=MIDDLE  ALT=\"600Tw+%2B+550Ta+=+2900\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "we simplify (ii) to be <BR>\n" );
document.write( "(iii) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12Tw+%2B+11Ta+=+58 ALIGN=MIDDLE  ALT=\"12Tw+%2B+11Ta+=+58\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "multiply (i) by -11 to get<BR>\n" );
document.write( "(iv) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-11Tw+-+11Ta+=+-55 ALIGN=MIDDLE  ALT=\"-11Tw+-+11Ta+=+-55\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "adding (iii) and (iv) we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Tw+=+3 ALIGN=MIDDLE  ALT=\"Tw+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "or 3 hours flying with the wind.<BR>\n" );
document.write( "This means that <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Ta+=+2 ALIGN=MIDDLE  ALT=\"Ta+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "or 2 hours flying against the wind. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );