document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=536711>Question 536711</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a bus traveled 10km/h faster, it would take 2 hours less time to make a 315km trip. What is its speed?\r<BR>\n" );
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document.write( "Thanks for any help:) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #352619 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=352619\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If a bus traveled 10km/h faster, it would take 2 hours less time to make a 315km trip.<BR>\n" );
document.write( "What is its speed?<BR>\n" );
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document.write( "Let s = the speed of the bus<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+10) = the faster speed<BR>\n" );
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document.write( "Write time equation, time = dist/speed<BR>\n" );
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document.write( "Actual time - faster time = 2 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2Fs ALIGN=MIDDLE  ALT=\"315%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2F%28%28s%2B10%29%29 ALIGN=MIDDLE  ALT=\"315%2F%28%28s%2B10%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2<BR>\n" );
document.write( "multiply by s(s+10)<BR>\n" );
document.write( "s(s+10)*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2Fs ALIGN=MIDDLE  ALT=\"315%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - s(s+5)*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2F%28%28s%2B10%29%29 ALIGN=MIDDLE  ALT=\"315%2F%28%28s%2B10%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2s(s+10)<BR>\n" );
document.write( "Cancel the denominators and you have<BR>\n" );
document.write( "315(s+10) - 315s = 2s^2 + 20s<BR>\n" );
document.write( "315s + 3150 - 315s = 2s^2 + 20s<BR>\n" );
document.write( "0 = 2s^2 + 20s - 3150<BR>\n" );
document.write( "Simplify, divide by 2<BR>\n" );
document.write( "s^2 + 10s - 1575 = 0<BR>\n" );
document.write( "Factors to<BR>\n" );
document.write( "(s+45)(s-35) = 0<BR>\n" );
document.write( "The positive solution<BR>\n" );
document.write( "s = 35 mph is the actual bus speed<BR>\n" );
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document.write( "Check this by finding the times at each speed<BR>\n" );
document.write( "315/35 = 9 hrs<BR>\n" );
document.write( "315/45 = 7 hrs<BR>\n" );
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