document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=637219>Question 637219</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Quadratic functions are often used in economics to represent both the production cost function and the revenue function. Suppose that the cost C, in dollars of producing x mobile phones is given by \r<BR>\n" );
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document.write( " C(x) = 400 +8x + 0.1x2\r<BR>\n" );
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document.write( "Whilst the revenue function R, also in dollars is \r<BR>\n" );
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document.write( " R(x) = x(32 = 0.1x)<BR>\n" );
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document.write( "A point where the cost and the revenue are equal is called a break-even point. \r<BR>\n" );
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document.write( "(a) How many mobile phones need to be produced to break even? You must use algebra to answer this question. \r<BR>\n" );
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document.write( "(b) Find the cost(s) and revenue(s) corresponding to your solution(s) to part (a). \r<BR>\n" );
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document.write( "(c) Draw the graphs of both functions on the same set of axes for the domain 0 &#8804; x &#8804; 150. <BR>\n" );
document.write( "Clearly indicate on your graph where all your solutions to parts (a) and (b) are. This graph may be drawn by hand or with software. Give your graph a title and label its axes appropriately. <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #401503 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=401503\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "a) <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE C(x)\ =\ R(x)\">, so:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ 0.1x^2\ +8x\ +\ 400\ =\ ???\">\r<BR>\n" );
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document.write( "Can't finish because of your typo in the defintion of R(x).  Put in the correct definition of R(x), then solve for <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE x_e\">\r<BR>\n" );
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document.write( "b) Evaluate <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE C(x_e)\"> and <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE R(x_e)\">\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it<BR>\n" );
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