document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=890173>Question 890173</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a car travels 20 kph faster than a truck. it covers 350 km in two hours less than the time it takes for the truck to travel the same distance. what is the speed of both vehicles? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #538818 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=538818\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a car travels 20 kph faster than a truck.<BR>\n" );
document.write( " it covers 350 km in two hours less than the time it takes for the truck to travel the same distance.<BR>\n" );
document.write( " what is the speed of both vehicles?<BR>\n" );
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document.write( "Let s = the speed of the truck<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+20) = the speed of the car<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation time = dist/speed<BR>\n" );
document.write( ";<BR>\n" );
document.write( "Truck time - car time = 2 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=350%2Fs ALIGN=MIDDLE  ALT=\"350%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=350%2F%28%28s%2B20%29%29 ALIGN=MIDDLE  ALT=\"350%2F%28%28s%2B20%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2<BR>\n" );
document.write( "Multiply the equation b s(s+20), cancel the denominators, and you have<BR>\n" );
document.write( "350(s+20) - 350s = 2s(s+20)<BR>\n" );
document.write( "350s + 7000 - 350s = 2s^2 + 40s<BR>\n" );
document.write( "Combine to form a quadratic equation<BR>\n" );
document.write( "2s^2 + 40s - 7000 = 0<BR>\n" );
document.write( "Simplify divide by 2<BR>\n" );
document.write( "s^2 + 20s - 3500 = 0<BR>\n" );
document.write( "Factors to <BR>\n" );
document.write( "(s+70)(s-50) = 0<BR>\n" );
document.write( "the positive solution is what we want here<BR>\n" );
document.write( "s = 50 km/h is the speed of the truck<BR>\n" );
document.write( "then obviously;<BR>\n" );
document.write( "70 km is the speed of the car<BR>\n" );
document.write( ":<BR>\n" );
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document.write( "Confirm this by finding the travel time of each<BR>\n" );
document.write( "350/50 = 7 hrs<BR>\n" );
document.write( "350/70 = 5 hrs<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "differ: 2 hrs<BR>\n" );
document.write( " <BR>\n" );
document.write( ":<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );