document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1072067>Question 1072067</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 780-mile, 7-hour plane trip was flown at two speeds. For the first part of the trip, the average speed was 105 mph. <BR>\n" );
document.write( "For the remainder of the trip, the average speed was 120 mph. How long did the plane fly at each speed?\r<BR>\n" );
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document.write( "105 mph  	 <BR>\n" );
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document.write( "120 mph  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #686964 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52793)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=686964\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "A 780-mile, 7-hour plane trip was flown at two speeds. For the first part of the trip, the average speed was 105 mph. <BR>\n" );
document.write( "For the remainder of the trip, the average speed was 120 mph. How long did the plane fly at each speed?\r<BR>\n" );
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document.write( "105 mph  	 <BR>\n" );
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document.write( "120 mph <BR>\n" );
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document.write( "<B>Solution 1</U>  (system of two equations)\r<BR>\n" );
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document.write( "   x +     y =  7,       (1)    (x is time flying at 105 mph; y is time flying at 120 mph)\r\n" );
document.write( "105x + 120y = 780.       (2)\r\n" );
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document.write( "Express x = 7-y from (1) and substitute into (2), then solve or y.\r\n" );
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document.write( "<U>Solution 2</U>  (one equation)\r<BR>\n" );
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document.write( "105*x _ 120*(7-x) = 780.\r\n" );
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document.write( "Solve for x.\r\n" );
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