document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=648179>Question 648179</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At 10:30 am two planes leave Houston, one flying east at 560 km/h and the other flying west at 640 km/h. At what time will they be 2100 km apart? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #406592 by </B><A HREF=/tutors/aboutme.mpl?userid=DrBeeee><B>DrBeeee(684)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=DrBeeee><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=406592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let t = the amount of time the planes travel<BR>\n" );
document.write( "Let d1 = distance travelled by east bound plane<BR>\n" );
document.write( "Let d2 = distance travelled by the west bound plane<BR>\n" );
document.write( "Formula to use<BR>\n" );
document.write( "(1) d = r*t, where d is the distance travelled, km, in time t, hr, when travelling at a rate of r km/hr<BR>\n" );
document.write( "For the first plane<BR>\n" );
document.write( "(2) d1 = 560*t<BR>\n" );
document.write( "For the second plane <BR>\n" );
document.write( "(3) d2 = 640*t<BR>\n" );
document.write( "The total distance travelled or distance apart after t hr is<BR>\n" );
document.write( "(4) d1 + d2 = 2100<BR>\n" );
document.write( "Substituting (2) and (3) into (4) yields<BR>\n" );
document.write( "(5) 560*t + 640*t = 2100 or<BR>\n" );
document.write( "(6) 1200*t = 2100 or<BR>\n" );
document.write( "(7) t = 7/4<BR>\n" );
document.write( "Answer: The planes will be 2100km apart at 12:15pm. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );