document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1052968>Question 1052968</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The monthly cost (in dollars) of water use is a linear function of the amount of water used (in hundreds of cubic feet, HCF). The cost for using <BR>\n" );
document.write( "16<BR>\n" );
document.write( " HCF of water is <BR>\n" );
document.write( "$31.47<BR>\n" );
document.write( ", and the cost for using <BR>\n" );
document.write( "35<BR>\n" );
document.write( " HCF is <BR>\n" );
document.write( "$64.72<BR>\n" );
document.write( ". What is the cost for using <BR>\n" );
document.write( "25<BR>\n" );
document.write( " HCF of water?\r<BR>\n" );
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document.write( "WaterusageinHCF<BR>\n" );
document.write( "Monthlycostindollars<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #668268 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39616)</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=668268\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Two ordered pair,  (16, 31.47) and (35, 64.72), would be part of a linear equation.  You placed your question in \"Algebra: Systems of Linear Equations\".\r<BR>\n" );
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document.write( "Use formula for slope, and the point-slope form equation of a line (not the only way).\r<BR>\n" );
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document.write( "Picking the first point with x=16,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y-31.47=%28%2864.72-31.47%29%2F%2835-16%29%29%28x-16%29 ALIGN=MIDDLE  ALT=\"y-31.47=%28%2864.72-31.47%29%2F%2835-16%29%29%28x-16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Simplify that and form into y as a function of x. </SPAN>\n" );
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