document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=824129>Question 824129</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose that the height (in centimeters) of a candle is a linear function of the amount of time (in hours) it has been burning. After 7 hours of burning, a candle has a height of 22.8centimeters. After 21 hours of burning, its height is14.4 centimeters. What is the height of the candle after 12 hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #496115 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=496115\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This same question has occurred a few weeks ago.\r<BR>\n" );
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document.write( "Identify two data points (x, y).  Since the description indicates the function to be height of the candle, use x as burn time, and y as height.  The two points then are (7, 22.8) and (21, 14.4).  \r<BR>\n" );
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document.write( "We want y=mx+b equation form.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m=%2814.4-22.8%29%2F%2821-7%29=-8.4%2F14=highlight%28-3%2F5%29 ALIGN=MIDDLE  ALT=\"m=%2814.4-22.8%29%2F%2821-7%29=-8.4%2F14=highlight%28-3%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Rearranging to have b, <BR>\n" );
document.write( "b=y-mx<BR>\n" );
document.write( "Use EITHER identified point<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=14.4-%28-3%2F5%2921=14.4%2B%283%2F5%2921=highlight%2827%29 ALIGN=MIDDLE  ALT=\"b=14.4-%28-3%2F5%2921=14.4%2B%283%2F5%2921=highlight%2827%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "The equation for height versus burn time is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=-%283%2F5%29x%2B27%29 ALIGN=MIDDLE  ALT=\"highlight%28y=-%283%2F5%29x%2B27%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Your objective to finish is find y when x=12. </SPAN>\n" );
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