document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=661215>Question 661215</A>: <I><SPAN STYLE=\"word-break: break-all;\"> (FLIGHT CONDITIONS) In stable air, the air temperature drops about 5 °(F) for each 1,000-foot rise in altitude.\r<BR>\n" );
document.write( "\n" );
document.write( "(A) If the temperature at sea level is 100 °F and a commercial pilot reports a temperature of -30 °F at 26000 feet, write a linear equation that expresses temperature T in terms of altitude A.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #411561 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=411561\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Plot altitude on the horizontal and temp on the vertical<BR>\n" );
document.write( "so, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+T+=+f%28A%29+ ALIGN=MIDDLE  ALT=\"+T+=+f%28A%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The slope of the line will be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-5+%2F+1000+ ALIGN=MIDDLE  ALT=\"+-5+%2F+1000+\"   DISABLED_style= \"max-width:90%; height:auto;\" > degrees/feet<BR>\n" );
document.write( "You are given 2 points on the line,<BR>\n" );
document.write( "( 0, 100 ) the sea level temp, and<BR>\n" );
document.write( "( 26000, -30 ) <BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "slope = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+-30+-+100+%29+%2F+%28+26000+-+0+%29+ ALIGN=MIDDLE  ALT=\"+%28+-30+-+100+%29+%2F+%28+26000+-+0+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "slope = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-130+%2F+26000+ ALIGN=MIDDLE  ALT=\"+-130+%2F+26000+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "slope = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-+.005+=+-5%2F1000+ ALIGN=MIDDLE  ALT=\"-+.005+=+-5%2F1000+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This agrees with the given slope<BR>\n" );
document.write( "---------------------------<BR>\n" );
document.write( "Using the point-slope formula:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+T+-+100+%29+%2F+%28+A+-+0+%29+=+-.005+ ALIGN=MIDDLE  ALT=\"+%28+T+-+100+%29+%2F+%28+A+-+0+%29+=+-.005+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+T+-+100+=+-.005A+ ALIGN=MIDDLE  ALT=\"+T+-+100+=+-.005A+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+T+=+-.005A+%2B+100+ ALIGN=MIDDLE  ALT=\"+T+=+-.005A+%2B+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" > answer<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "does it go through (26000, -30) ?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+T+=+-.005A+%2B+100+ ALIGN=MIDDLE  ALT=\"+T+=+-.005A+%2B+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-30+=+-.005%2A26000+%2B+100+ ALIGN=MIDDLE  ALT=\"+-30+=+-.005%2A26000+%2B+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-30+=+-130+%2B+100+ ALIGN=MIDDLE  ALT=\"+-30+=+-130+%2B+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-30+=+-30+ ALIGN=MIDDLE  ALT=\"+-30+=+-30+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK<BR>\n" );
document.write( "Here's the plot with the horizontal axis expressed<BR>\n" );
document.write( "in thousands of feet<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+400%2C+400%2C+-10%2C+50%2C+-50%2C+200%2C+-5x+%2B+100+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+400%2C+400%2C+-10%2C+50%2C+-50%2C+200%2C+-5x+%2B+100+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );