document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1046376>Question 1046376</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At a cruising speed,Marie's small family plane can fly at 100 km/h. On a recent vacation trip, it took 3 h to fly with the wind to a resort and 7 h to fly back against the wind. What was the rate of the wind? How far away was the resort?<BR>\n" );
document.write( "Please help me.<BR>\n" );
document.write( "I'm not understanding uniform motion problems. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #661843 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=661843\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> R is a constant rate.<BR>\n" );
document.write( "D for Distance<BR>\n" );
document.write( "T for Time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D%2FT=R ALIGN=MIDDLE  ALT=\"D%2FT=R\"   DISABLED_style= \"max-width:90%; height:auto;\" > ----------You can also include the units and see how they fit with the numbers for left member and right member.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Multiply the two members by  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2FT ALIGN=MIDDLE  ALT=\"1%2FT\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you have.......   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D=RT ALIGN=MIDDLE  ALT=\"D=RT\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "The basic travel rate rule for constant rate of travel is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=RT=D ALIGN=MIDDLE  ALT=\"RT=D\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "The meaning of \"speed\" in your example problem can be assumed as \"rate\", because any angle is not really important for the example here.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<u>SOLUTION</u>______________________________\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Analyzing and solving your example best is handled by assigning variables and putting data into a table.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "The wind's speed and the trip distance are not known.  The wind going in the same direction as the plane will ADD to the plane's speed,<BR>\n" );
document.write( "but the same wind with its same speed will SUBTRACT from the plane's speed while flying against this wind.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Variables are assigned according to what is shown in this table:<BR>\n" );
document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "                    SPEED            TIME             DISTANCE\r\n" );
document.write( "\r\n" );
document.write( "GOING               100+w             3                  d \r\n" );
document.write( "\r\n" );
document.write( "FLY BACK            100-w             7                  d\r\n" );
document.write( "\r\n" );
document.write( "</PRE>\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "SYSTEM OF EQUATIONS BASED ON THE UNIFORM TRAVEL RATE RULE:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28%28100%2Bw%29%2A3=d%2C%28100-w%29%2A7=d%29 ALIGN=MIDDLE  ALT=\"system%28%28100%2Bw%29%2A3=d%2C%28100-w%29%2A7=d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Solve that system.<BR>\n" );
document.write( "Notice you have two expressions for d, so substituting, you simply equate the two expressions for d.  This is not the only way<BR>\n" );
document.write( "but it is more efficient.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28100%2Bw%293=%28100-w%297 ALIGN=MIDDLE  ALT=\"%28100%2Bw%293=%28100-w%297\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=300%2B3w=700-7w ALIGN=MIDDLE  ALT=\"300%2B3w=700-7w\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3w%2B300=-7w%2B700 ALIGN=MIDDLE  ALT=\"3w%2B300=-7w%2B700\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3w%2B300%2B7w-300=-7w%2B700%2B7w-300 ALIGN=MIDDLE  ALT=\"3w%2B300%2B7w-300=-7w%2B700%2B7w-300\"   DISABLED_style= \"max-width:90%; height:auto;\" >------just applying additive inverses,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10w=400 ALIGN=MIDDLE  ALT=\"10w=400\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28w=40%29 ALIGN=MIDDLE  ALT=\"highlight%28w=40%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "You can evaluate d on your own. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );