document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=811795>Question 811795</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a truck drives north at 60 mph, one-and-half hour later a car  drives in the the same direction at 70 mph . for how many hours must the car drive for it to be 50 miles ahead of the truck.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #488904 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=488904\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The truck's head start is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+60%2A1.5+=+90+ ALIGN=MIDDLE  ALT=\"+60%2A1.5+=+90+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the driving time for the car when<BR>\n" );
document.write( "it is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+50+ ALIGN=MIDDLE  ALT=\"+50+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi ahead of the truck<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+ ALIGN=MIDDLE  ALT=\"+d+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the distance the car travels<BR>\n" );
document.write( "when it meets the truck<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "Equation for truck:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+-+90+=+60t+ ALIGN=MIDDLE  ALT=\"+d+-+90+=+60t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation for car:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+70t+ ALIGN=MIDDLE  ALT=\"+d+=+70t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "------------<BR>\n" );
document.write( "By substitution:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+70t+-+90+=+60t+ ALIGN=MIDDLE  ALT=\"+70t+-+90+=+60t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+10t+=+90+ ALIGN=MIDDLE  ALT=\"+10t+=+90+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+9+ ALIGN=MIDDLE  ALT=\"+t+=+9+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "------------<BR>\n" );
document.write( "In 9 hrs they meet<BR>\n" );
document.write( "From the place where they meet, let<BR>\n" );
document.write( "the car go <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d%5B2%5D+ ALIGN=MIDDLE  ALT=\"+d%5B2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi, and the<BR>\n" );
document.write( "truck go <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d%5B2%5D+-50+ ALIGN=MIDDLE  ALT=\"+d%5B2%5D+-50+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t%5B2%5D+ ALIGN=MIDDLE  ALT=\"+t%5B2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the time to do this<BR>\n" );
document.write( "truck's equation:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d%5B2%5D+-+50+=+60t%5B2%5D+ ALIGN=MIDDLE  ALT=\"+d%5B2%5D+-+50+=+60t%5B2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "car's equation:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d%5B2%5D+=+70t%5B2%5D+ ALIGN=MIDDLE  ALT=\"+d%5B2%5D+=+70t%5B2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+70t%5B2%5D+-+50+=+60t%5B2%5D+ ALIGN=MIDDLE  ALT=\"+70t%5B2%5D+-+50+=+60t%5B2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+10t%5B2%5D+=+50+ ALIGN=MIDDLE  ALT=\"+10t%5B2%5D+=+50+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t%5B2%5D+=+5+ ALIGN=MIDDLE  ALT=\"+t%5B2%5D+=+5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+%2B+t%5B2%5D+=+9+%2B+5+ ALIGN=MIDDLE  ALT=\"+t+%2B+t%5B2%5D+=+9+%2B+5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "It takes 14 hrs for the car to get 50 mi ahead <BR>\n" );
document.write( "of the truck\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );