document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=847065>Question 847065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me solve this word problem using two variables. I have tried but i only know how to use one variable, not two. \r<BR>\n" );
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document.write( "A car and bike set out at noon from the same point and head in the same direction. At 1:00 P.M, the car is 60 km ahead of the bike. Find how fast each travels, given that the car travels four times as fast as the bike </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #510179 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=510179\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> here's a solution with 2 variables:<BR>\n" );
document.write( "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;\" > = he speed of the bike<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4s+ ALIGN=MIDDLE  ALT=\"+4s+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the speed of the car<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+ ALIGN=MIDDLE  ALT=\"+d+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the distance in km the bike travels in 1 hour<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+%2B+60+ ALIGN=MIDDLE  ALT=\"+d+%2B+60+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the distance the car travels in 1 hour<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "Equation for the bike:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+s%2A1+ ALIGN=MIDDLE  ALT=\"+d+=+s%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation for the car:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+%2B+60+=+4s%2A1+ ALIGN=MIDDLE  ALT=\"+d+%2B+60+=+4s%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "--------------------<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+%2B+60+=+4s%2A1+ ALIGN=MIDDLE  ALT=\"+s+%2B+60+=+4s%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3s+=+60+ ALIGN=MIDDLE  ALT=\"+3s+=+60+\"   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+=+20+ ALIGN=MIDDLE  ALT=\"+s+=+20+\"   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=+4s+=+80+ ALIGN=MIDDLE  ALT=\"+4s+=+80+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The bike travels 20 km/hr<BR>\n" );
document.write( "The car travels 80 km/hr<BR>\n" );
document.write( "------------------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+s%2A1+ ALIGN=MIDDLE  ALT=\"+d+=+s%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+20+ ALIGN=MIDDLE  ALT=\"+d+=+20+\"   DISABLED_style= \"max-width:90%; height:auto;\" > km<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+%2B+60+=+4s%2A1+ ALIGN=MIDDLE  ALT=\"+d+%2B+60+=+4s%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+%2B+60+=+4%2A20%2A1+ ALIGN=MIDDLE  ALT=\"+d+%2B+60+=+4%2A20%2A1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+80+-+60+ ALIGN=MIDDLE  ALT=\"+d+=+80+-+60+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+20+ ALIGN=MIDDLE  ALT=\"+d+=+20+\"   DISABLED_style= \"max-width:90%; height:auto;\" > km<BR>\n" );
document.write( "OK<BR>\n" );
document.write( "Note that you can say <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+d+ ALIGN=MIDDLE  ALT=\"+y+=+d+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x+=+s+ ALIGN=MIDDLE  ALT=\"+x+=+s+\"   DISABLED_style= \"max-width:90%; height:auto;\" > in order to plot <BR>\n" );
document.write( "on x-y plane\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );