document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=210935>Question 210935</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A vendor has learned that by pricing hot dogs at $1.00, sales will reach 135 hot dogs per day. Raising the price to $1.60 causes sales to fall to 105 hot dogs per day. Let y be the number of hot dogs the vendor sells when they're priced at x dollars. Write a linear equation that models sales as a function of price.\r<BR>\n" );
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document.write( "Guidelines:\r<BR>\n" );
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document.write( "1. What two 'points' (x-value, y-value pairs) are we given?\r<BR>\n" );
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document.write( "2. What is the slope of the line connecting these points?\r<BR>\n" );
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document.write( "3. Use the formula:\r<BR>\n" );
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document.write( "y – {some point's y-value} = m * ( x - {some point's x-value} ) to derive the equation\r<BR>\n" );
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document.write( "(note: some point's y-value and some point's x-value must be the respective x and y values of the same point)\r<BR>\n" );
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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 #159399 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=159399\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A vendor has learned that by pricing hot dogs at $1.00, sales will reach 135 hot dogs per day. <BR>\n" );
document.write( "Raising the price to $1.60 causes sales to fall to 105 hot dogs per day. <BR>\n" );
document.write( "Let y be the number of hot dogs the vendor sells when they're priced at x dollars. <BR>\n" );
document.write( "Write a linear equation that models sales as a function of price.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Guidelines:<BR>\n" );
document.write( "1. What two 'points' (x-value, y-value pairs) are we given?<BR>\n" );
document.write( "x1 = 1.00; y1 = 135<BR>\n" );
document.write( "x2 = 1.60; y2 = 105<BR>\n" );
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document.write( "2. What is the slope of the line connecting these points?<BR>\n" );
document.write( "The slope formula: m = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28y2-y1%29%2F%28x2-x1%29 ALIGN=MIDDLE  ALT=\"%28y2-y1%29%2F%28x2-x1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "m = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28105-135%29%2F%281.6-1%29 ALIGN=MIDDLE  ALT=\"%28105-135%29%2F%281.6-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-30%29%2F.6 ALIGN=MIDDLE  ALT=\"%28-30%29%2F.6\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -50 is the slope<BR>\n" );
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document.write( "3. Use the formula:<BR>\n" );
document.write( "y – {some point's y-value} = m * ( x - {some point's x-value} ) to derive the equation<BR>\n" );
document.write( "(note: some point's y-value and some point's x-value must be the respective x and y values of the same point)<BR>\n" );
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document.write( "y - 135 = -50(x - 1) <BR>\n" );
document.write( "y - 135 = -50x + 50<BR>\n" );
document.write( "y = -50x + 50 + 135<BR>\n" );
document.write( "y = -50x + 185  </SPAN>\n" );
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