document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204831>Question 1204831</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane made a two-way flight from Miami to Dublin.  The trip from Miami to Dublin took four more hours than the return trip from Dublin to Miami.  The cause for the difference in flight times were winds over the ocean, which averaged 50 km/hr on the return trip.  Assume there was no wind on the trip to Dublin.  The total distance travelled both ways was 9900 km. Let x represent the average speed of the plane in still air (no wind).<BR>\n" );
document.write( "a) Represent time going from Dublin to Miami as a rational expression.<BR>\n" );
document.write( "b) Represent the time going from Miami to Dublin as a rational expression.<BR>\n" );
document.write( "c) Write an equation representing the relationships between the times.<BR>\n" );
document.write( "d) What was the average rate of the plane in still air.<BR>\n" );
document.write( "e) How long did the round trip take? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #841338 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39625)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=841338\">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( "                 SPEED      TIME      DISTANCE\r\n" );
document.write( "GOING TO           r        x+4       9900/2=4950\r\n" );
document.write( "COMEING BACK       r+50     x         9900/2=4950\r\n" );
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document.write( "</PRE><BR>\n" );
document.write( "Note that the variables here were assigned differently than your exercise instructed to do.  x here is time for the return trip and r is for speed of the plane absent of any wind.  Notice, no wind involved for the return trip.<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28rx%2B4r=4950%2Crx%2B50x=4950%29 ALIGN=MIDDLE  ALT=\"system%28rx%2B4r=4950%2Crx%2B50x=4950%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4950-4r=4950-50x ALIGN=MIDDLE  ALT=\"4950-4r=4950-50x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4r=50x ALIGN=MIDDLE  ALT=\"4r=50x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2r=25x ALIGN=MIDDLE  ALT=\"2r=25x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=25x%2F2 ALIGN=MIDDLE  ALT=\"r=25x%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "substiture r in first equation.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2825x%2F2%29x%2B4%2825x%2F2%29=4950 ALIGN=MIDDLE  ALT=\"%2825x%2F2%29x%2B4%2825x%2F2%29=4950\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2825%2F2%29x%5E2%2B%284%2A25%2F2%29x-4950=0 ALIGN=MIDDLE  ALT=\"%2825%2F2%29x%5E2%2B%284%2A25%2F2%29x-4950=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28x%5E2%2B4x-396=0%29 ALIGN=MIDDLE  ALT=\"highlight_green%28x%5E2%2B4x-396=0%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-4%2B-+sqrt%2816%2B4%2A396%29%29%2F2 ALIGN=MIDDLE  ALT=\"x=%28-4%2B-+sqrt%2816%2B4%2A396%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > must use the positive s.r.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-4%2Bsqrt%2816%2B4%2A396%29%29%2F2 ALIGN=MIDDLE  ALT=\"x=%28-4%2Bsqrt%2816%2B4%2A396%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-4%2Bsqrt%281600%29%29%2F2 ALIGN=MIDDLE  ALT=\"x=%28-4%2Bsqrt%281600%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-4%2B40%29%2F2=-2%2B20=22 ALIGN=MIDDLE  ALT=\"x=%28-4%2B40%29%2F2=-2%2B20=22\"   DISABLED_style= \"max-width:90%; height:auto;\" >--------<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=22%29 ALIGN=MIDDLE  ALT=\"highlight%28x=22%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >------Time hours for the return trip.<BR>\n" );
document.write( "Therefore <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=25x%2F2 ALIGN=MIDDLE  ALT=\"r=25x%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=25%2A22%2F2=25%2A11 ALIGN=MIDDLE  ALT=\"r=25%2A22%2F2=25%2A11\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28r=275%29 ALIGN=MIDDLE  ALT=\"highlight%28r=275%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >---------speed of plane if no wind\r<BR>\n" );
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document.write( "TIME for total round trip, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=22%2B4%2B22=highlight%2848%2Ahours%29 ALIGN=MIDDLE  ALT=\"22%2B4%2B22=highlight%2848%2Ahours%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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