document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=558130>Question 558130</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A passenger plane flew to moscow and back. The trip there took five hours and the trip back took nine hours.  It averaged 144 km/h faster on the trip there than on the return trip.  Find the passenger plane's average speed on the outbound trip.\r<BR>\n" );
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document.write( "O.k so I did have a go at it Trying to use a system of equations using the substitution method to eliminate one unknown but it didn't work.  I will try and explain what I was playing around with:\r<BR>\n" );
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document.write( "D1 = Distance there  D2 = Distance back ( but not sure if I needed this as it is same Distance )<BR>\n" );
document.write( "Average Speed = S  \r<BR>\n" );
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document.write( "D1/5 + D2/9 = S\r<BR>\n" );
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document.write( "D1/5 = D2/9+144 ( I tried substituting this in )\r<BR>\n" );
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document.write( "D2/9+144 + D2/9 = S ( then I combined the like terms )\r<BR>\n" );
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document.write( "D2/18+144 = s ( but this is where I realized I had failed as I still had 2 variables.\r<BR>\n" );
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document.write( "Please help me someone I am so bad at word problems and I would love to be confident at them. \r<BR>\n" );
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document.write( "P.S I wasn't sure about which was the outbound trip, I guessed it meant the trip back.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #852287 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10555)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=852287\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "A passenger plane flew to moscow and back. The trip there took five hours and the trip back took nine hours.  It averaged 144 km/h faster on the trip there than on the return trip.  Find the passenger plane's average speed on the outbound trip.\r\n" );
document.write( "\r\n" );
document.write( "O.k so I did have a go at it Trying to use a system of equations using the substitution method to eliminate one unknown but it didn't work.  I will try and explain what I was playing around with:\r\n" );
document.write( "\r\n" );
document.write( "D1 = Distance there  D2 = Distance back ( but not sure if I needed this as it is same Distance )\r\n" );
document.write( "Average Speed = S  \r\n" );
document.write( "\r\n" );
document.write( "D1/5 + D2/9 = S\r\n" );
document.write( "\r\n" );
document.write( "D1/5 = D2/9+144 ( I tried substituting this in )\r\n" );
document.write( "\r\n" );
document.write( "D2/9+144 + D2/9 = S ( then I combined the like terms )\r\n" );
document.write( "\r\n" );
document.write( "D2/18+144 = s ( but this is where I realized I had failed as I still had 2 variables.\r\n" );
document.write( "\r\n" );
document.write( "Please help me someone I am so bad at word problems and I would love to be confident at them. \r\n" );
document.write( "\r\n" );
document.write( "P.S I wasn't sure about which was the outbound trip, I guessed it meant the trip back.\r\n" );
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document.write( "No!! The OUTBOUND trip is the one to Moscow, while the one back from Moscow is the INBOUND/RETURN trip.\r\n" );
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document.write( "Let OUTBOUND speed, be S\r\n" );
document.write( "Then INBOUND/RETURN speed = S - 144\r\n" );
document.write( "It took 5 hours to get there, so distance traveled to Moscow = 5S\r\n" );
document.write( "It took 9 hours to get back, so distance on return trip = 9(S - 144)\r\n" );
document.write( "Since distance there and back is the same, we get 5S = 9(S - 144)\r\n" );
document.write( "                                                  5S = 9S - 9(144)\r\n" );
document.write( "                                             4S - 9S = - 9(144)\r\n" );
document.write( "                                                - 4S = - 9(144)\r\n" );
document.write( "                Average speed on the OUTBOUND, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28matrix%281%2C9%2C+S%2C+%22=%22%2C+%28-+9%28144%29%29%2F%28-+4%29%2C+%22=%22%2C+9%2836cross%28-+144%29%29%2Fcross%28%28-+4%29%29%2C+%22=%22%2C+9%2836%29%2C+%22=%22%2C+highlight%28matrix%281%2C2%2C+324%2C+%22km%2Fh%22%29%29%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ></PRE> </SPAN>\n" );
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