document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=757743>Question 757743</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a plane flies 2000 mile in 8 hours, with a tailwind all the way. The return trip on the same route, now with a headwind, takes 10 hours. Assume both remain constant, find the speed of the plane and the speed of the wind. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #461069 by </B><A HREF=/tutors/aboutme.mpl?userid=tasmart><B>tasmart(9)</B></A><img src=\"/images/stars/stars-05.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tasmart><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=tasmart><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=461069\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> tailwind  speed of plain plus speed of wind p+w\r<BR>\n" );
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document.write( "headwind speed of plain minus speed of wind p-w\r<BR>\n" );
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document.write( "8 hours times p+w=2000<BR>\n" );
document.write( "10 hours times p-w=2000<BR>\n" );
document.write( "systems of equations with two variables.\r<BR>\n" );
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document.write( "8(p+w)=2000<BR>\n" );
document.write( "10(p-w)=2000\r<BR>\n" );
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document.write( "distribute:<BR>\n" );
document.write( "8p+8w=2000<BR>\n" );
document.write( "10p-10w=2000\r<BR>\n" );
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document.write( "8p=2000-8w<BR>\n" );
document.write( "p=250-w\r<BR>\n" );
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document.write( "now substitution:<BR>\n" );
document.write( "10p-10w=2000<BR>\n" );
document.write( "10(250-w)-10w=2000<BR>\n" );
document.write( "2500-10w-10w=2000<BR>\n" );
document.write( "-20w=2000-2500<BR>\n" );
document.write( "-20w=-500<BR>\n" );
document.write( "w=-500/-20<BR>\n" );
document.write( "w=25 miles speed of wind.\r<BR>\n" );
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document.write( "8p+8(25)=2000<BR>\n" );
document.write( "8p+200=2000<BR>\n" );
document.write( "8p=2000-200<BR>\n" );
document.write( "8p=1800<BR>\n" );
document.write( "p=1800/8<BR>\n" );
document.write( "p=225 speed of plain.\r<BR>\n" );
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document.write( "8(225)+8(25)=2000 <BR>\n" );
document.write( "200+1800=2000\r<BR>\n" );
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document.write( "10(225)-10(25)=2000<BR>\n" );
document.write( "2250-250=2000<BR>\n" );
document.write( "speed of wind is 25mph speed of plain is 225mph\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );