document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=988491>Question 988491</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An airplane flies between Boston and Cleveland. During a round-trip flight, the plane flew a distance of 630 mi each way. The trip with a tailwind took 3 hours. The return trip agains the wind took 3.5 hours. Find the speed of the wind. Find the speed of the plane in still air<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #609024 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=609024\">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=+w+ ALIGN=MIDDLE  ALT=\"+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  = windspeed in mi/hr<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;\" > = the speed of the plane in still air<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+%2B+w+ ALIGN=MIDDLE  ALT=\"+s+%2B+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = plane's speed going with the wind<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+-+w+ ALIGN=MIDDLE  ALT=\"+s+-+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = plane's speed going against the wind<BR>\n" );
document.write( "---------------------------------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+%28+s+%2B+w+%29%2A3+ ALIGN=MIDDLE  ALT=\"+630+=+%28+s+%2B+w+%29%2A3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+%28+s+-+w+%29%2A3.5+ ALIGN=MIDDLE  ALT=\"+630+=+%28+s+-+w+%29%2A3.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "----------------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+%2B+w+=+210+ ALIGN=MIDDLE  ALT=\"+s+%2B+w+=+210+\"   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+-+w+=+180+ ALIGN=MIDDLE  ALT=\"+s+-+w+=+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" > ( now add equations )<BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2s+=+390+ ALIGN=MIDDLE  ALT=\"+2s+=+390+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+195+ ALIGN=MIDDLE  ALT=\"+s+=+195+\"   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+%2B+w+=+210+ ALIGN=MIDDLE  ALT=\"+s+%2B+w+=+210+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+195+%2B+w+=+210+ ALIGN=MIDDLE  ALT=\"+195+%2B+w+=+210+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+w+=+15+ ALIGN=MIDDLE  ALT=\"+w+=+15+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "The windspeed is 15 mi/hr<BR>\n" );
document.write( "The speed of th plane in still air is 195 mi/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=+630+=+%28+s+%2B+w+%29%2A3+ ALIGN=MIDDLE  ALT=\"+630+=+%28+s+%2B+w+%29%2A3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+%28+195+%2B+15+%29%2A3+ ALIGN=MIDDLE  ALT=\"+630+=+%28+195+%2B+15+%29%2A3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+210%2A3+ ALIGN=MIDDLE  ALT=\"+630+=+210%2A3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+630+ ALIGN=MIDDLE  ALT=\"+630+=+630+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+%28+s+-+w+%29%2A3.5+ ALIGN=MIDDLE  ALT=\"+630+=+%28+s+-+w+%29%2A3.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+%28+195+-+15+%29%2A3.5+ ALIGN=MIDDLE  ALT=\"+630+=+%28+195+-+15+%29%2A3.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+180%2A3.5+ ALIGN=MIDDLE  ALT=\"+630+=+180%2A3.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+630+=+630+ ALIGN=MIDDLE  ALT=\"+630+=+630+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );