document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=209784>Question 209784</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A passenger plane and a jet leave at the same time from the same airport, traveling in opposite directions. The jet travels at twice the speed of the passenger plane. They are 2400 miles apart in 4 hours. Find the speed of the passenger plane and jet. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #158577 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=158577\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> write 2 equations, 1 for the passenger plane<BR>\n" );
document.write( "and 1 for the jet<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D\"   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=d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D ALIGN=MIDDLE  ALT=\"d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "given:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bj%5D+=+2r%5Bp%5D ALIGN=MIDDLE  ALT=\"r%5Bj%5D+=+2r%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bj%5D+%2B+d%5Bp%5D+=+2400 ALIGN=MIDDLE  ALT=\"d%5Bj%5D+%2B+d%5Bp%5D+=+2400\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5Bj%5D+=+4 ALIGN=MIDDLE  ALT=\"t%5Bj%5D+=+4\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5Bp%5D+=+4 ALIGN=MIDDLE  ALT=\"t%5Bp%5D+=+4\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "---------------------------<BR>\n" );
document.write( "Now I can rewrite the equations:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+r%5Bp%5D%2A4 ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+r%5Bp%5D%2A4\"   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=d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D ALIGN=MIDDLE  ALT=\"d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2400+-+d%5Bp%5D+=+2%2Ar%5Bp%5D%2A4 ALIGN=MIDDLE  ALT=\"2400+-+d%5Bp%5D+=+2%2Ar%5Bp%5D%2A4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-d%5Bp%5D+=+8r%5Bp%5D+-+2400 ALIGN=MIDDLE  ALT=\"-d%5Bp%5D+=+8r%5Bp%5D+-+2400\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+2400+-+8r%5Bp%5D ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+2400+-+8r%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "By substitution:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4r%5Bp%5D+=+2400+-+8r%5Bp%5D ALIGN=MIDDLE  ALT=\"4r%5Bp%5D+=+2400+-+8r%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12r%5Bp%5D+=+2400 ALIGN=MIDDLE  ALT=\"12r%5Bp%5D+=+2400\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bp%5D+=+200 ALIGN=MIDDLE  ALT=\"r%5Bp%5D+=+200\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bj%5D+=+2r%5Bp%5D ALIGN=MIDDLE  ALT=\"r%5Bj%5D+=+2r%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bj%5D+=+2%2A200 ALIGN=MIDDLE  ALT=\"r%5Bj%5D+=+2%2A200\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5Bj%5D+=+400 ALIGN=MIDDLE  ALT=\"r%5Bj%5D+=+400\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "The speed of the passenger plane is 200 mi/hr<BR>\n" );
document.write( "The speed of the jet is 400 mi/hr<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+r%5Bp%5D%2At%5Bp%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+200%2A4 ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+200%2A4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+=+800 ALIGN=MIDDLE  ALT=\"d%5Bp%5D+=+800\"   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=d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D ALIGN=MIDDLE  ALT=\"d%5Bj%5D+=+r%5Bj%5D%2At%5Bj%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bj%5D+=+400%2A4 ALIGN=MIDDLE  ALT=\"d%5Bj%5D+=+400%2A4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bj%5D+=+1600 ALIGN=MIDDLE  ALT=\"d%5Bj%5D+=+1600\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+%2B+d%5Bj%5D+=+800+%2B+1600 ALIGN=MIDDLE  ALT=\"d%5Bp%5D+%2B+d%5Bj%5D+=+800+%2B+1600\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5Bp%5D+%2B+d%5Bj%5D+=+2400 ALIGN=MIDDLE  ALT=\"d%5Bp%5D+%2B+d%5Bj%5D+=+2400\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
document.write( "OK  <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );