document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=316076>Question 316076</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose that the credit remaining on a phone card (in dollars) is a linear function of the total calling time (in minutes). When graphed, the function gives a line with a slope of -0.15  See the figure below.\r<BR>\n" );
document.write( "\n" );
document.write( "There is 34.05 in credit remaining on the card after 27 minutes of calls. How much credit will there be after 34 minutes of calls?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #226108 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=226108\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "You are given the slope of a straight line and a point<BR>\n" );
document.write( "on that line. Credit remaining is plotted on the y-axis<BR>\n" );
document.write( "and total calling time is on the x-axis<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+-.15 ALIGN=MIDDLE  ALT=\"m+=+-.15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(x,y) = (27,34.05) <BR>\n" );
document.write( "the formula to use is:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28y+-+y%5B1%5D%29%2F%28x+-+x%5B1%5D%29 ALIGN=MIDDLE  ALT=\"m+=+%28y+-+y%5B1%5D%29%2F%28x+-+x%5B1%5D%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.15+=+%28y+-+34.05%29%2F%28x+-+27%29 ALIGN=MIDDLE  ALT=\"-.15+=+%28y+-+34.05%29%2F%28x+-+27%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.15%2A%28x+-+27%29+=+y+-+34.05 ALIGN=MIDDLE  ALT=\"-.15%2A%28x+-+27%29+=+y+-+34.05\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.15x+%2B+4.05+=+y+-+34.05 ALIGN=MIDDLE  ALT=\"-.15x+%2B+4.05+=+y+-+34.05\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-.15x+%2B+38.1 ALIGN=MIDDLE  ALT=\"y+=+-.15x+%2B+38.1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now solve for y, given the point (34,y)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-.15%2A34+%2B+38.1 ALIGN=MIDDLE  ALT=\"y+=+-.15%2A34+%2B+38.1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-5.1+%2B+38.1 ALIGN=MIDDLE  ALT=\"y+=+-5.1+%2B+38.1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+33 ALIGN=MIDDLE  ALT=\"y+=+33\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "There is $33 credit after 34 min of calls\r<BR>\n" );
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document.write( "  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );