document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=251841>Question 251841</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A and B, traveling at respective rates of a and b kilometers per hour, head directly towards each other across a distance of 120 kilometers. If both start at 10:30 a.m., they will meet at noon. If A starts at 10:00 a.m. and B starts at 11:00 a.m., they will also meet at noon. Find the ordered pair (a,b).\r<BR>\n" );
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document.write( "a) (30,30) b) (30,40) c) (40,40) d) (40,30) e) none of these </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #183556 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=183556\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A and B, traveling at respective rates of a and b kilometers per hour, head directly towards each other across a distance of 120 kilometers. If both start at 10:30 a.m., they will meet at noon. If A starts at 10:00 a.m. and B starts at 11:00 a.m., they will also meet at noon. Find the ordered pair (a,b). <BR>\n" );
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document.write( "When a meets b, their total travel dist = 120 km;<BR>\n" );
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document.write( "Travel time of both starting at 1:30: 1.5 hrs<BR>\n" );
document.write( "When a starts at 10: 2 hrs<BR>\n" );
document.write( "When b starts at 11: 1 hr<BR>\n" );
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document.write( "Write two distance equations; Dist = speed * time<BR>\n" );
document.write( "1.5a + 1.5b = 120<BR>\n" );
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document.write( "2a + 1b = 120<BR>\n" );
document.write( "or<BR>\n" );
document.write( "b = 120-2a<BR>\n" );
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document.write( "Substitute above for b in the 1st equation, find a<BR>\n" );
document.write( "1.5a + 1.5(120-2a) = 120<BR>\n" );
document.write( "1.5a + 180 - 3a = 120<BR>\n" );
document.write( "1.5a - 3a = 120 - 180<BR>\n" );
document.write( "-1.5a = -60<BR>\n" );
document.write( "a = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-60%29%2F%28-1.5%29 ALIGN=MIDDLE  ALT=\"%28-60%29%2F%28-1.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "a = 40<BR>\n" );
document.write( "and<BR>\n" );
document.write( "b = 120 - 2(40)<BR>\n" );
document.write( "b = 120 - 80<BR>\n" );
document.write( "b = 40 <BR>\n" );
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document.write( "Ordered pair, 40,40<BR>\n" );
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document.write( "Check solution in 2nd equation<BR>\n" );
document.write( "2(40) + 1(40) = 120 </SPAN>\n" );
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