document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=16537>Question 16537</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am not sure where to ask this.  This is not a quadratic equation, but here is the problem.\r<BR>\n" );
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document.write( "A company uses the function C(x)= 0.2X^2-3.4x+150 to model the unit cost in dollars for producing x bars.  For what number of bars is the unit cost at its minimum?  What is the unit cost at that level of production?\r<BR>\n" );
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document.write( "I guess I want to solve for C but I don't see two equations here.  By using the brute force method, I get the lowest cost to be at 27 bars and a cost of 7.555555555 repeating. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #8073 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=8073\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the cost function for producing x bars is <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C%28x%29+=+0.2X%5E2-3.4x%2B150+ ALIGN=MIDDLE  ALT=\"C%28x%29+=+0.2X%5E2-3.4x%2B150+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then to find the cost per bar, you must divide this by x.\r<BR>\n" );
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document.write( "Cost per bar= <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%280.2X%5E2-3.4x%2B150+%29%2Fx ALIGN=MIDDLE  ALT=\"%280.2X%5E2-3.4x%2B150+%29%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" >  or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.2x+-3.4+%2B150x%5E%28-1%29+ ALIGN=MIDDLE  ALT=\"0.2x+-3.4+%2B150x%5E%28-1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "If you are in a calculus class (probably Calculus for Businees Majors or Concepts of Calculus!), then you take the derivative of this. <BR>\n" );
document.write( "Deriv = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.2+-150x%5E%28-2%29+ ALIGN=MIDDLE  ALT=\".2+-150x%5E%28-2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Set derivative = zero, and solve for x:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.2+-150x%5E%28-2%29+=+0 ALIGN=MIDDLE  ALT=\".2+-150x%5E%28-2%29+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.2+-+150%2F%28x%5E2%29+=+0+ ALIGN=MIDDLE  ALT=\".2+-+150%2F%28x%5E2%29+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.2+=+150%2F%28x%5E2%29+ ALIGN=MIDDLE  ALT=\".2+=+150%2F%28x%5E2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Multiply both sides by the LCD <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2 ALIGN=MIDDLE  ALT=\"x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.2x%5E2+=+150+ ALIGN=MIDDLE  ALT=\".2x%5E2+=+150+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Divide by .2<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+=+150%2F.2+=+750 ALIGN=MIDDLE  ALT=\"x%5E2+=+150%2F.2+=+750\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Square root both sides, where x>0:<BR>\n" );
document.write( "x= sqrt(750)= 27.386\r<BR>\n" );
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document.write( "Unit cost= <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%280.2X%5E2-3.4x%2B150+%29%2Fx ALIGN=MIDDLE  ALT=\"%280.2X%5E2-3.4x%2B150+%29%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" >  <BR>\n" );
document.write( "Unit cost (when x= 27 bars) = 7.55555. . .\r<BR>\n" );
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document.write( "R^2 at SCC<BR>\n" );
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