document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1098121>Question 1098121</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The marginal cost (C) of manufacturing x cell phones (in thousands) is given by: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C%28x%29=+5x%5E2-200x%2B4000 ALIGN=MIDDLE  ALT=\"C%28x%29=+5x%5E2-200x%2B4000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "A. How many cell phones should be manufactured to minimize the marginal cost? <BR>\n" );
document.write( "B. What is the minimum marginal cost? \r<BR>\n" );
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document.write( "My work was = <BR>\n" );
document.write( "A. Using <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-b%2F2a ALIGN=MIDDLE  ALT=\"-b%2F2a\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-200%29%2F%282%29%285%29 ALIGN=MIDDLE  ALT=\"%28-200%29%2F%282%29%285%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >= 20 or 20,000 phones to minimize the marginal cost. <BR>\n" );
document.write( "B. I subbed in 20 as the x value in the given equation resulting in the minimum marginal cost being $2000. \r<BR>\n" );
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document.write( "I am uncertain if this is how to approach the question. <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 #712520 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=712520\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Yes, your approach is fine.<BR>\n" );
document.write( "-b/2a is the approach to get the vertex of the minimum, and it does equal 20, or 20,000 phones.<BR>\n" );
document.write( "5(20^2)-200(20)+4000=2000-4000+4000=$2000<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-10%2C30%2C-1000%2C10000%2C5x%5E2-200x%2B4000%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-10%2C30%2C-1000%2C10000%2C5x%5E2-200x%2B4000%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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