document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=211587>Question 211587</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780495558880/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me with this uniform motion problem? If the speed were increased by 10mph, a 420 mile trip would take 1 hr less time. How long will the trip take at the slower speed? Please show me all the steps and please get back to me before Tues. 10am. <BR>\n" );
document.write( "Thank you guys </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #159871 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=159871\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Distance+=+Rate%2ATime ALIGN=MIDDLE  ALT=\"Distance+=+Rate%2ATime\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You are told the distance is 420 miles.<BR>\n" );
document.write( "Let the slow speed be represented by s (in miles per hours) and the slow time be represented by t (in hours)<BR>\n" );
document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420+=+s+%2A+t ALIGN=MIDDLE  ALT=\"420+=+s+%2A+t\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "Thus <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420%2Ft+=+s ALIGN=MIDDLE  ALT=\"420%2Ft+=+s\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You are told that at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%2B10 ALIGN=MIDDLE  ALT=\"s%2B10\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the time will be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t-1 ALIGN=MIDDLE  ALT=\"t-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420+=+%28s%2B10%29%28t-1%29 ALIGN=MIDDLE  ALT=\"420+=+%28s%2B10%29%28t-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now substitute in the value you found for s above<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420+=+%28%28420%2Ft%29+%2B+10%29+%2A+%28t-1%29 ALIGN=MIDDLE  ALT=\"420+=+%28%28420%2Ft%29+%2B+10%29+%2A+%28t-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420+=+%28420%2B10t%29%2Ft+%2A+%28t-1%29 ALIGN=MIDDLE  ALT=\"420+=+%28420%2B10t%29%2Ft+%2A+%28t-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420t+=+%28420%2B10t%29+%2A+%28t-1%29 ALIGN=MIDDLE  ALT=\"420t+=+%28420%2B10t%29+%2A+%28t-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=420t+=+420t++-420+%2B+10t%5E2+-10t ALIGN=MIDDLE  ALT=\"420t+=+420t++-420+%2B+10t%5E2+-10t\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+10t%5E2+-10t+-+420 ALIGN=MIDDLE  ALT=\"0+=+10t%5E2+-10t+-+420\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+t%5E2+-+t+-42 ALIGN=MIDDLE  ALT=\"0+=+t%5E2+-+t+-42\"   DISABLED_style= \"max-width:90%; height:auto;\" >  factor this or use the quadratic equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+%28t-7%29%28t%2B6%29 ALIGN=MIDDLE  ALT=\"0+=+%28t-7%29%28t%2B6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "For a product to equal 0, one or more of the terms multiplied must be 0. So<BR>\n" );
document.write( "either <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t-7=0 ALIGN=MIDDLE  ALT=\"t-7=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > ot <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2B6+=+0 ALIGN=MIDDLE  ALT=\"t%2B6+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > that means either<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=7 ALIGN=MIDDLE  ALT=\"t=7\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <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;\" > since the time cannot be negative, the time at the slow speed must be 7 hours.\r<BR>\n" );
document.write( "\n" );
document.write( "Now check your answers. If the time is 7 hours then the slow speed must be 60mph<BR>\n" );
document.write( "If the speed if 10mph faster, then the faster speed is 70mph. <BR>\n" );
document.write( "At 70mph, the time is 420/70 = 6 hours. Which is an hour faster.<BR>\n" );
document.write( "So there you have it.<BR>\n" );
document.write( "happy Labor day -- and still int time for 10am tomorrow </SPAN>\n" );
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