document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1047415>Question 1047415</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Susan is driving on the highway. She begins the trip with <BR>\n" );
document.write( "18<BR>\n" );
document.write( " gallons of gas in her car. The car uses up one gallon of gas every <BR>\n" );
document.write( "25<BR>\n" );
document.write( " miles.<BR>\n" );
document.write( "Let <BR>\n" );
document.write( "G<BR>\n" );
document.write( " represent the number of gallons of gas she has left in her tank, and let <BR>\n" );
document.write( "D<BR>\n" );
document.write( " represent the total distance (in miles) she has traveled. Write an equation relating <BR>\n" );
document.write( "G<BR>\n" );
document.write( " to <BR>\n" );
document.write( "D<BR>\n" );
document.write( ", and then graph your equation using the axes below </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #663097 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</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=663097\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Rate is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2825%2F1%29%28miles%2Fgallon%29 ALIGN=MIDDLE  ALT=\"%2825%2F1%29%28miles%2Fgallon%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F25%29%28gallons%2Fmiles%29 ALIGN=MIDDLE  ALT=\"%281%2F25%29%28gallons%2Fmiles%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "G, amount of fuel in gallons, in the tank.<BR>\n" );
document.write( "Initial data point, ordered pair as (D,G), would be (0,18).<BR>\n" );
document.write( "You want an expression to calculate G gallons of gasoline (or fuel), so pick the slope  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F25%29%28gallons%2Fmiles%29 ALIGN=MIDDLE  ALT=\"%281%2F25%29%28gallons%2Fmiles%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  The data point identified is an axis intercept, on the vertical axis  (meaning on the G axis).\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28G=-%281%2F25%29D%2B18%29 ALIGN=MIDDLE  ALT=\"highlight%28G=-%281%2F25%29D%2B18%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The slope is really negative because the car is consuming amount of fuel, not gaining amount of fuel. </SPAN>\n" );
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