document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=132449>Question 132449</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780321443625/algebrahomeworkh>Intermediate Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A freight train and an express train leave towns 390 km apart, traveling toward one another. The freight train travels 30 km per hour slower than the express train. They pass one another 3 hrs. later. What are their speeds? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #96823 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=96823\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I set up <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%2At ALIGN=MIDDLE  ALT=\"d+=+r%2At\"   DISABLED_style= \"max-width:90%; height:auto;\" > for both trains<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f ALIGN=MIDDLE  ALT=\"f\"   DISABLED_style= \"max-width:90%; height:auto;\" > = freight train<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=e ALIGN=MIDDLE  ALT=\"e\"   DISABLED_style= \"max-width:90%; height:auto;\" > = express train<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+r%5Be%5D%2At%5Be%5D ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+r%5Be%5D%2At%5Be%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bf%5D+=+r%5Bf%5D%2At%5Bf%5D ALIGN=MIDDLE  ALT=\"d%5Bf%5D+=+r%5Bf%5D%2At%5Bf%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5Be%5D+=+3 ALIGN=MIDDLE  ALT=\"t%5Be%5D+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5Bf%5D+=+3 ALIGN=MIDDLE  ALT=\"t%5Bf%5D+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "They both travel for 3 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+%2B+d%5Bf%5D+=+390 ALIGN=MIDDLE  ALT=\"d%5Be%5D+%2B+d%5Bf%5D+=+390\"   DISABLED_style= \"max-width:90%; height:auto;\" >km<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bf%5D+=+390+-+d%5Be%5D ALIGN=MIDDLE  ALT=\"d%5Bf%5D+=+390+-+d%5Be%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bf%5D+=+r%5Be%5D+-+30 ALIGN=MIDDLE  ALT=\"r%5Bf%5D+=+r%5Be%5D+-+30\"   DISABLED_style= \"max-width:90%; height:auto;\" > km/hr<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+r%5Be%5D%2A3 ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+r%5Be%5D%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=390+-+d%5Be%5D+=+%28r%5Be%5D+-+30%29%2A3 ALIGN=MIDDLE  ALT=\"390+-+d%5Be%5D+=+%28r%5Be%5D+-+30%29%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=390+-+d%5Be%5D+=+3%2Ar%5Be%5D+-+90 ALIGN=MIDDLE  ALT=\"390+-+d%5Be%5D+=+3%2Ar%5Be%5D+-+90\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+480+-+3%2Ar%5Be%5D ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+480+-+3%2Ar%5Be%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "substitute this for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D ALIGN=MIDDLE  ALT=\"d%5Be%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > in (1)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2Ar%5Be%5D+=+480+-+3%2Ar%5Be%5D ALIGN=MIDDLE  ALT=\"3%2Ar%5Be%5D+=+480+-+3%2Ar%5Be%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2Ar%5Be%5D+=+480 ALIGN=MIDDLE  ALT=\"6%2Ar%5Be%5D+=+480\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Be%5D+=+80 ALIGN=MIDDLE  ALT=\"r%5Be%5D+=+80\"   DISABLED_style= \"max-width:90%; height:auto;\" > km/hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bf%5D+=+r%5Be%5D+-+30 ALIGN=MIDDLE  ALT=\"r%5Bf%5D+=+r%5Be%5D+-+30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bf%5D+=+80+-+30 ALIGN=MIDDLE  ALT=\"r%5Bf%5D+=+80+-+30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bf%5D+=+50 ALIGN=MIDDLE  ALT=\"r%5Bf%5D+=+50\"   DISABLED_style= \"max-width:90%; height:auto;\" > km/hr<BR>\n" );
document.write( "The freight train's speed is 50 km/hr<BR>\n" );
document.write( "The express train's speed is 80 km/hr<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+r%5Be%5D%2A3 ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+r%5Be%5D%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+80%2A3 ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+80%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Be%5D+=+240+km ALIGN=MIDDLE  ALT=\"d%5Be%5D+=+240+km\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=390+-+d%5Be%5D+=+%28r%5Be%5D+-+30%29%2A3 ALIGN=MIDDLE  ALT=\"390+-+d%5Be%5D+=+%28r%5Be%5D+-+30%29%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=390+-+240+=+%2880+-+30%29%2A3 ALIGN=MIDDLE  ALT=\"390+-+240+=+%2880+-+30%29%2A3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150+=+150 ALIGN=MIDDLE  ALT=\"150+=+150\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );