document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=593862>Question 593862</A>: <I><SPAN STYLE=\"word-break: break-all;\"> PLEASE HELP!!  I don't understand how to figure this out. Do I have to find the vertex? Put it in a quadratic equation???? \r<BR>\n" );
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document.write( "Parker’s Skateboard Shop has determined that when x skateboards are built, the average cost C per skateboard is given by C=x^2-80x+1625  .  How many skateboards should the shop build in order to minimize the average cost per skateboard?\r<BR>\n" );
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document.write( "Tips:  Since # skateboards = x in our situation, find the x-value of the minimum (vertex).\r<BR>\n" );
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document.write( "What is the minimum average cost?\r<BR>\n" );
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document.write( "Tips: Plug in 2a into cost equation </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #376512 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=376512\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the vertex is on the axis of symmetry\r<BR>\n" );
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document.write( "x = -b / (2a) = 80 / (2 * 1) = 40\r<BR>\n" );
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document.write( "C = 40^2 - 80(40) + 1625 </SPAN>\n" );
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