document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1104571>Question 1104571</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A new plane cruises at a speed of 400 m.p.h. If it makes a trip in 7<BR>\n" );
document.write( "hours with a strong wind and the return trip against the same wind in 9<BR>\n" );
document.write( "hours, how fast was the wind? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #719272 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=719272\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> speed=400<BR>\n" );
document.write( "wind=w<BR>\n" );
document.write( "(400+w)7=7w+2800<BR>\n" );
document.write( "(400-w)9=-9w+3600<BR>\n" );
document.write( "those are equal, since they are the same distance<BR>\n" );
document.write( "so 7w+2800=-9w+3600<BR>\n" );
document.write( "16w=800<BR>\n" );
document.write( "w=50 mph<BR>\n" );
document.write( "450 mph with the wind*7 hours is 3150 miles<BR>\n" );
document.write( "350 mph against the wind*9 hours is 3150 miles </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );