document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=334674>Question 334674</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane flying the 3020-mile trip from City A to City B has a 60 mph tailwind. The flights point of no return is the point at which the flight time required to return to City A is the same as the time required to continue to City B. If the speed of the plane in still air is 430 mph, how far from City A is the point of no return? I need to translate the problem into a pair of linear equations in two variables.<BR>\n" );
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document.write( "Ok, I have a line:<BR>\n" );
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document.write( "                                          3020 miles<BR>\n" );
document.write( "City A -------------------------------------------- City B<BR>\n" );
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document.write( "I know d = rt<BR>\n" );
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document.write( "and the distance is 3020 miles.<BR>\n" );
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document.write( "So it is rt = 3020, but with the 60 mph tailwind and 430 mph and all that I am just confused. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #239825 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=239825\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane flying the 3020-mile trip from City A to City B has a 60 mph tailwind.<BR>\n" );
document.write( " The flights point of no return is the point at which the flight time required<BR>\n" );
document.write( " to return to City A is the same as the time required to continue to City B.<BR>\n" );
document.write( " If the speed of the plane in still air is 430 mph, how far from City A is the point of no return? <BR>\n" );
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document.write( "Not sure why you need two variables here.<BR>\n" );
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document.write( ">>>>>>>>>>>>60 mph wind>>>>>>>>>>>>>>><BR>\n" );
document.write( "A-------------p-----------------------B<BR>\n" );
document.write( "|----------------3020 mi--------------|<BR>\n" );
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document.write( "Let p = the distance from A to the point of no return<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(3020-p) = the distance from B to the point of no return<BR>\n" );
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document.write( "430 + 60 = 490 mph; effective speed with the wind (continue to B)<BR>\n" );
document.write( "and<BR>\n" );
document.write( "430 - 60 = 370 mph; effective speed against the wind (return to A)<BR>\n" );
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document.write( "Write a time equation, Time = dist/speed<BR>\n" );
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document.write( "Time to return to A = Time to continue to B<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%2F370 ALIGN=MIDDLE  ALT=\"p%2F370\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283020-p%29%2F490 ALIGN=MIDDLE  ALT=\"%283020-p%29%2F490\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cross multiply<BR>\n" );
document.write( "490p = 370(3020-p)<BR>\n" );
document.write( "490p = 1117400 - 370p<BR>\n" );
document.write( "490p + 370p = 1117400<BR>\n" );
document.write( "860p = 1117400<BR>\n" );
document.write( "p = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1117400%2F860 ALIGN=MIDDLE  ALT=\"1117400%2F860\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "p = 1299.3 mi from A is the point of no return<BR>\n" );
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document.write( "See if this is true, find the time from p to A & B<BR>\n" );
document.write( "dist to B = 3020 - 1299.3 = 1720.7<BR>\n" );
document.write( "1299.3/370 = 3.51 hrs back to A<BR>\n" );
document.write( "1720.7/490 = 3.51 hrs to B </SPAN>\n" );
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