document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=114462>Question 114462</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The cost of producing a number of items x is given by C=mx+b, in which b is the fixed cost and m is the variable cost (the cost of producing one more item).<BR>\n" );
document.write( "(a). If the fixed cost is $40 and the variable cost is $10, write the cost equation.<BR>\n" );
document.write( "(b). Graph the cost equation. <BR>\n" );
document.write( "I am really lost on how to figure this out, I would so appreciate some help.\r<BR>\n" );
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document.write( "Thank You,<BR>\n" );
document.write( "Barb Neely </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #83287 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=83287\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You are given that the Cost equation is C(x) = mx + b <BR>\n" );
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document.write( "Furthermore you are told that b is the fixed cost and it is $40<BR>\n" );
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document.write( "Substitute this into the cost equation for b and the Cost equation becomes:<BR>\n" );
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document.write( "C(x) = mx + 40<BR>\n" );
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document.write( "And you are told that m is the variable cost of producing one more item and that it is $10.<BR>\n" );
document.write( "Substitute 10 for m and the equation is then:<BR>\n" );
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document.write( "C(x) = 10x + 40<BR>\n" );
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document.write( "This equation is the answer to part (a) of the problem.<BR>\n" );
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document.write( "To graph this equation, you plot the cost C on the y-axis and the number of units produced<BR>\n" );
document.write( "on the x-axis. Note that it only makes sense to have the values of x (the number of units<BR>\n" );
document.write( "produced) equal to 0 or a positive number. [How would you build or produce a negative<BR>\n" );
document.write( "number of units?] Therefore, the Cost will always be a positive number. On the y-axis the<BR>\n" );
document.write( "cost will be a minimum of $40 even if you produce no units. So the graph will start at $40<BR>\n" );
document.write( "on the y-axis (at the (x, y) point (0, 40) and will increase from there as the number of <BR>\n" );
document.write( "units produced increases.<BR>\n" );
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document.write( "You can get several points on the graph by assuming values for x and calculating the corresponding<BR>\n" );
document.write( "values for the Cost on the y-axis. For example, if 1 unit is produced (that is x = 1) the<BR>\n" );
document.write( "corresponding cost is given by the Cost equation as:<BR>\n" );
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document.write( "C(x) = 10(1) + 40 = 10 + 40 = 50<BR>\n" );
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document.write( "So the (x, y) point (1, 50) is another point on the graph.<BR>\n" );
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document.write( "Next you could assume that 5 units are produced ... that is x = 5. Substitute that value<BR>\n" );
document.write( "into the cost equation and you have:<BR>\n" );
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document.write( "C(x) = 10(5) + 40 = 50 + 40 = 90<BR>\n" );
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document.write( "This means that the (x, y) point (5, 90) is on the graph.<BR>\n" );
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document.write( "That is three points on the graph. You can plot these three points and then extend a straight <BR>\n" );
document.write( "line through them to sketch the graph. When you do that you should should have a graph that<BR>\n" );
document.write( "looks like:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28600%2C600%2C-2%2C+20%2C+-4%2C+250%2C10x+%2B+40%29 ALIGN=MIDDLE  ALT=\"graph%28600%2C600%2C-2%2C+20%2C+-4%2C+250%2C10x+%2B+40%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Ignore that part of the graph that shows in the area where x is negative. The graph should<BR>\n" );
document.write( "not extend to the left of the y-axis.<BR>\n" );
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document.write( "Hope this helps you to understand the problem a little better and to see your way through<BR>\n" );
document.write( "to the answers.<BR>\n" );
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