document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=959641>Question 959641</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A tour bus normally leaves for its destination at 5:00 p.m. for a 330 mile trip. This week however, the bus leaves at 5:30 p.m. To arrive on time, the driver drives 5 miles per hour faster than usual. What is the bus` usual speed?\r<BR>\n" );
document.write( "\n" );
document.write( "I did my best, it was not good enough </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #586535 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=586535\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+ ALIGN=MIDDLE  ALT=\"+s+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the usual speed in mi/hr that will result <BR>\n" );
document.write( "in the bus arriving on time<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 time in hours that the trip takes<BR>\n" );
document.write( "when the bus has speed <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+ ALIGN=MIDDLE  ALT=\"+s+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "----------------------------------------------<BR>\n" );
document.write( "Equation for a normal trip:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+s%2At+ ALIGN=MIDDLE  ALT=\"+330+=+s%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation for trip leaving at 5:30 PM<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+%28+s+%2B+5+%29%2A%28+t+-+.5+%29+ ALIGN=MIDDLE  ALT=\"+330+=+%28+s+%2B+5+%29%2A%28+t+-+.5+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "---------------------------------<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+s%2At+%2B+5t+-+.5s+-+2.5+ ALIGN=MIDDLE  ALT=\"+330+=+s%2At+%2B+5t+-+.5s+-+2.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+332.5+=+s%2At+%2B+5t+-+.5s+ ALIGN=MIDDLE  ALT=\"+332.5+=+s%2At+%2B+5t+-+.5s+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+330%2Ft+ ALIGN=MIDDLE  ALT=\"+s+=+330%2Ft+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "By substitution:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+332.5++=+330+%2B+5t+-+.5%2A%28+330%2Ft+%29+ ALIGN=MIDDLE  ALT=\"+332.5++=+330+%2B+5t+-+.5%2A%28+330%2Ft+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2.5+=+5t+-+165%2Ft+ ALIGN=MIDDLE  ALT=\"+2.5+=+5t+-+165%2Ft+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5t%5E2+-+2.5t+-+165+=+0+ ALIGN=MIDDLE  ALT=\"+5t%5E2+-+2.5t+-+165+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2.5+ ALIGN=MIDDLE  ALT=\"+2.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2t%5E2+-+t+-+66+=+0+ ALIGN=MIDDLE  ALT=\"+2t%5E2+-+t+-+66+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Use quadratic formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+2+ ALIGN=MIDDLE  ALT=\"+a+=+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+-1+ ALIGN=MIDDLE  ALT=\"+b+=+-1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+=+-66+ ALIGN=MIDDLE  ALT=\"+c+=+-66+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2+-+4%2A2%2A%28-66%29+%29%29+%2F+%282%2A2%29+ ALIGN=MIDDLE  ALT=\"+t+=+%28+-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2+-+4%2A2%2A%28-66%29+%29%29+%2F+%282%2A2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+1+%2B-+sqrt%28+1+%2B+528+%29%29+%2F+4+ ALIGN=MIDDLE  ALT=\"+t+=+%28+1+%2B-+sqrt%28+1+%2B+528+%29%29+%2F+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+1+%2B-+sqrt%28+529+%29%29+%2F+4+ ALIGN=MIDDLE  ALT=\"+t+=+%28+1+%2B-+sqrt%28+529+%29%29+%2F+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+%28+1+%2B+23+%29+%2F+4+ ALIGN=MIDDLE  ALT=\"+t+=+%28+1+%2B+23+%29+%2F+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+24%2F4+ ALIGN=MIDDLE  ALT=\"+t+=+24%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+6+ ALIGN=MIDDLE  ALT=\"+t+=+6+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+330%2Ft+ ALIGN=MIDDLE  ALT=\"+s+=+330%2Ft+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+330%2F6+ ALIGN=MIDDLE  ALT=\"+s+=+330%2F6+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+55+ ALIGN=MIDDLE  ALT=\"+s+=+55+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The usual speed is 55 mi/hr<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+%28+s+%2B+5+%29%2A%28+t+-+.5+%29+ ALIGN=MIDDLE  ALT=\"+330+=+%28+s+%2B+5+%29%2A%28+t+-+.5+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+%28+55+%2B+5+%29%2A%28+6+-+.5+%29+ ALIGN=MIDDLE  ALT=\"+330+=+%28+55+%2B+5+%29%2A%28+6+-+.5+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+60%2A5.5+ ALIGN=MIDDLE  ALT=\"+330+=+60%2A5.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+330+=+330+ ALIGN=MIDDLE  ALT=\"+330+=+330+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );