document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195183>Question 1195183</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose that the weight (in pounds) of an airplane is a linear function of the total amount of fuel (in qallons) in its tank. When graphed, the function gives a line<BR>\n" );
document.write( "with a slope of 5.5. See the figure below.<BR>\n" );
document.write( "With 47 gallons of fuel in its tank, the airplane has a weight of 2258.5 pounds. What is the weight of the plane with 13 gallons of fuel in its tank?<BR>\n" );
document.write( "2258.5<BR>\n" );
document.write( "Airplane<BR>\n" );
document.write( "weight<BR>\n" );
document.write( "(in pounds)<BR>\n" );
document.write( "pounds<BR>\n" );
document.write( "×<BR>\n" );
document.write( "S<BR>\n" );
document.write( "P<BR>\n" );
document.write( "Amount of fuel </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #827585 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=827585\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> linear equation is y = mx + b<BR>\n" );
document.write( "m is the slope<BR>\n" );
document.write( "b is the y-intercept<BR>\n" );
document.write( "x is the number of gallons of fuel in the tank.<BR>\n" );
document.write( "y is the weight of the airplane.<BR>\n" );
document.write( "with a slope of 5.5, the equation becomes:<BR>\n" );
document.write( "y = 5.5 * x + b<BR>\n" );
document.write( "when x = 47, y = 2258.5<BR>\n" );
document.write( "equation becomes:<BR>\n" );
document.write( "2258.5 = 5.5 * 47 + b<BR>\n" );
document.write( "solve for b to get:<BR>\n" );
document.write( "b = 2258.5 - 5.5 * 47 = 2000.<BR>\n" );
document.write( "the equation becomes:<BR>\n" );
document.write( "y = 5.5 * x + 2000<BR>\n" );
document.write( "2000 is the weight of the plane with no fuel in it.<BR>\n" );
document.write( "when x = 47, the equation becomes:<BR>\n" );
document.write( "y = 5.5 * 47 + 2000 = 2258.5.<BR>\n" );
document.write( "this was the weight of the plane given in the statement of the problem, which confirms the equation is good.<BR>\n" );
document.write( "with 13 gallons of fuel in it, the equation becomes:<BR>\n" );
document.write( "y = 5.5 * 13 + 2000 = 2071.5<BR>\n" );
document.write( "that's your solution.\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );