math
posted by pam on .
the number of tickets sold each day for an upcoming performance is given by
N(x)=0.5x^2+13x+15 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?
Ticket sales peak ___ days after concert first announced.
The number of tickets sold on that day will be ______.

max at x = 13/(2* .5) = 13
Now just evaluate N(13)