document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=902222>Question 902222</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At sea level, the boiling point of water is 100°C. At an altitude of 5 km, the boiling point of water is 82.5°C. <BR>\n" );
document.write( "Write a linear function for the boiling point of water y in terms of the altitude above sea level x. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #547167 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=547167\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> at sea level the boiling point is 100 degrees centigrade.<BR>\n" );
document.write( "at 5km above sea level, the boiling point of water is 82.5 degrees centigrade.\r<BR>\n" );
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document.write( "let x = the number of km above sea level.\r<BR>\n" );
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document.write( "when x = 0, the boiling point is 100 degrees centigrade.\r<BR>\n" );
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document.write( "when x = 5 km, the boiling point is 82.5 degrees centigrade.\r<BR>\n" );
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document.write( "the average change in boiling point is equal to (82.5 - 100) / 5 which is equal to -17.5 / 5 which is equal to -3.5 degrees centigrade per kilometer.\r<BR>\n" );
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document.write( "the formula becomes:\r<BR>\n" );
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document.write( "y = -3.5*x + 100\r<BR>\n" );
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document.write( "when x = 0, y = 100<BR>\n" );
document.write( "when x = 5, y = 5*-3.5 = -17.5 + 100 = 82.5 degrees centigrade.\r<BR>\n" );
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document.write( "the graph looks like this:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2014/091602.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( "the slope of the line becomes the change in the value of y divided by the change in the value of x.\r<BR>\n" );
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document.write( "the change in the value of y is the change in the boiling point of water.<BR>\n" );
document.write( "the change in the value of x is the change in the number of kilometers above sea level.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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