document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=151427>Question 151427</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am very lost on this word problem. I don't even know where to begin. Could someone explain the steps to me? \r<BR>\n" );
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document.write( "A battery manufacturing plant spends C dollars per hour to produce \"D\" size batteries. An efficiency consultant has determined that C is related to the number of batteries produced per hour, x, according to the equation C(x)=0.01x^2 - 2.6x + 245. What number of batteries per hour minimizes the cost? \r<BR>\n" );
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document.write( "76, 130, 245 or 140 batteries. \r<BR>\n" );
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document.write( "Am I supposed to plug the number of batteries into the equation for x and solve?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #111337 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=111337\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> yes, you can substitute (plug in) to find the minimum value\r<BR>\n" );
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document.write( "another way is the fact that the minimum (or maximum) of a parabola (quadratic) is on the axis of symmetry\r<BR>\n" );
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document.write( "the general equation for the axis of symmetry is x=-b/(2a)\r<BR>\n" );
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document.write( "in this case __ x=-(-2.6)/[2(0.01)] __ x=130 </SPAN>\n" );
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