document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=548898>Question 548898</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The number of tickets sold each day for an upcoming performance of Handel's Messiah given by N(x)=-0.5x^2+15x+12, where x is the number of days since the concert was first announced. When will daily ticket sales peak and how many tickets will be sold that day? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #357280 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=357280\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> N(x)=-0.5x^2+15x+12\r<BR>\n" );
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document.write( "this is an inverted parabola since coefficient of x^2 is negative\r<BR>\n" );
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document.write( "x coordinate of vertex = -b/2a<BR>\n" );
document.write( "b=15, a=-0.5\r<BR>\n" );
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document.write( "-b/2a= -15/2(-0.5)= -15/-1 = 15\r<BR>\n" );
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document.write( "so sales will peak on the 15th day.\r<BR>\n" );
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document.write( "plug value of x in the equation to get the y coordinate of the vertex\r<BR>\n" );
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document.write( "((-0.5) * (15^2)) + (15 * 15) + 12 = 124.5<BR>\n" );
document.write( "maximum sales will be 124 on the 15th day </SPAN>\n" );
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