The number of tickets sold each day for an upcoming performance of Handel's Messiah is given by N(x)=-0.6x^2+12+13, 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?

Answer 1

N(x) = -0.6x^x+12x+13.

The above is the Eq of a parabola that
opens downwrd. Therefore, the max point
on the curve is the vertex:

Xv = -b/2a = -12 / -1.2 = 10 = The # of days.

In the original Eq, substitute 10 for
X to get # of tickets sold:

N(x) = (-0.6)10^2 + 12*10 + 13 = 73. =
The # of tickets sold.