the number of tickets sold for an upcoming concert is given by N(x)=-0.6x^2+13.2x+11 where x is the number of days since the concert was first announced.

Ticket sales will peak____?_____ days after the concert was first announced.

The number of ticket sold on that day will be__?___

Question

the number of tickets sold for an upcoming concert is given by N(x)=-0.6x^2+13.2x+11 where x is the number of days since the concert was first announced.

Ticket sales will peak____?_____ days after the concert was first announced.

The number of ticket sold on that day will be__?___

mertsj · Answer

We are talking about the vertex here.  x coordinate is -b/2a or -13.2/-1.2=11
Put that in for x and find that N(x) is 83.6
So 11 days after the concert is announced sales will peak at 83 tickets.

anonymous · Answer

I mean 84

mertsj · Answer

Why would one round 83.6 to 87?

mertsj · Answer

I don't think so because the parabola never reaches a height of 84 and since one cannot sell a fraction of a ticket, I think we should say that 83 would be sold.

anonymous · Answer

Thanks, I just hate to lose point for the tiny fraction!