document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=614456>Question 614456</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Doug and Austin both run on their junior high school cross country team. Doug was not feeling well and ran 2 miles per hour slower than Austin. Doug finished the four mile race 10 minutes after Austin. How fast was Austin running? How long did it take Doug to finish the race?\r<BR>\n" );
document.write( "\n" );
document.write( "this is what I have but it doesn't seem to be working out<BR>\n" );
document.write( "D = R x T<BR>\n" );
document.write( "Doug ... 4 ... x-2 ... [4/(x-2)]+10<BR>\n" );
document.write( "Austin ... 4 ... x ... 4/x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #386570 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=386570\">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;\" > = Austin's speed<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;\" > = Austin's time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+-+2+ ALIGN=MIDDLE  ALT=\"+s+-+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Doug's speed<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+%2B+1%2F6+ ALIGN=MIDDLE  ALT=\"+t+%2B+1%2F6+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Doug's time ( 1/6 hr = 10 min )<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+4+ ALIGN=MIDDLE  ALT=\"+d+=+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > It's a 4 mile race<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "Austin's equation:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4+=+s%2At+ ALIGN=MIDDLE  ALT=\"+4+=+s%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Doug's equation:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4+=+%28+s+-+2+%29%2A%28+t+%2B+1%2F6+%29+ ALIGN=MIDDLE  ALT=\"+4+=+%28+s+-+2+%29%2A%28+t+%2B+1%2F6+%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=+4+=+s%2At+-+2t+%2B+s%2F6+-+1%2F3+ ALIGN=MIDDLE  ALT=\"+4+=+s%2At+-+2t+%2B+s%2F6+-+1%2F3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%2F6+-+2t+=+4+%2B+1%2F3+-+s%2At+ ALIGN=MIDDLE  ALT=\"+s%2F6+-+2t+=+4+%2B+1%2F3+-+s%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute (1) into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%2F6+-+2t+=+4+%2B+1%2F3+-+4+ ALIGN=MIDDLE  ALT=\"+s%2F6+-+2t+=+4+%2B+1%2F3+-+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%2F6+-+2t+=+1%2F3+ ALIGN=MIDDLE  ALT=\"+s%2F6+-+2t+=+1%2F3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+-+12t+=+2+ ALIGN=MIDDLE  ALT=\"+s+-+12t+=+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "And also from (1):<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+4%2Fs+ ALIGN=MIDDLE  ALT=\"+t+=+4%2Fs+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substituting:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+-+12%2A%284%2Fs%29+=+2+ ALIGN=MIDDLE  ALT=\"+s+-+12%2A%284%2Fs%29+=+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+48+=+2s+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+48+=+2s+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5E2+-+2s+-+48+=+0+ ALIGN=MIDDLE  ALT=\"+s%5E2+-+2s+-+48+=+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=s+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"s+=+%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+=+1+ ALIGN=MIDDLE  ALT=\"+a+=+1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+-2+ ALIGN=MIDDLE  ALT=\"+b+=+-2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+=+-48+ ALIGN=MIDDLE  ALT=\"+c+=+-48+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A%28-48%29+%29%29%2F%282%2A1%29+ ALIGN=MIDDLE  ALT=\"s+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A%28-48%29+%29%29%2F%282%2A1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s+=+%28+2+%2B-+sqrt%28+4+%2B+192+%29%29+%2F+2+ ALIGN=MIDDLE  ALT=\"s+=+%28+2+%2B-+sqrt%28+4+%2B+192+%29%29+%2F+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s+=+%28+2+%2B-+sqrt%28+196+%29%29+%2F+2+ ALIGN=MIDDLE  ALT=\"s+=+%28+2+%2B-+sqrt%28+196+%29%29+%2F+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s+=+%28+2+%2B+14%29+%2F+2+ ALIGN=MIDDLE  ALT=\"s+=+%28+2+%2B+14%29+%2F+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+16%2F2+ ALIGN=MIDDLE  ALT=\"+s+=+16%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+8+ ALIGN=MIDDLE  ALT=\"+s+=+8+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Austin's speed was 8 mi/hr<BR>\n" );
document.write( "From (1):<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+4%2Fs+ ALIGN=MIDDLE  ALT=\"+t+=+4%2Fs+\"   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+=+4%2F8+ ALIGN=MIDDLE  ALT=\"+t+=+4%2F8+\"   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+=+1%2F2+ ALIGN=MIDDLE  ALT=\"+t+=+1%2F2+\"   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+1%2F6+ ALIGN=MIDDLE  ALT=\"+t+%2B+1%2F6+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Doug's time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+%2B+1%2F6+=+1%2F2+%2B+1%2F6+ ALIGN=MIDDLE  ALT=\"+t+%2B+1%2F6+=+1%2F2+%2B+1%2F6+\"   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+1%2F6+=+2%2F3+ ALIGN=MIDDLE  ALT=\"+t+%2B+1%2F6+=+2%2F3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%282%2F3%29%2A60+=+40+ ALIGN=MIDDLE  ALT=\"+%282%2F3%29%2A60+=+40+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "Doug's time is 2/3 hr, or 40 min<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4+=+%28+s+-+2+%29%2A%28+t+%2B+1%2F6+%29+ ALIGN=MIDDLE  ALT=\"+4+=+%28+s+-+2+%29%2A%28+t+%2B+1%2F6+%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=+4+=+%28+8+-+2+%29%2A%28+1%2F2+%2B+1%2F6+%29+ ALIGN=MIDDLE  ALT=\"+4+=+%28+8+-+2+%29%2A%28+1%2F2+%2B+1%2F6+%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=+4+=+6%2A%28+4%2F6+%29+ ALIGN=MIDDLE  ALT=\"+4+=+6%2A%28+4%2F6+%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=+4+=+4+ ALIGN=MIDDLE  ALT=\"+4+=+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );