Find the profit?

Question

The owner of a video store has determined that the profits P of the store are approximately given by where x is the number of videos rented daily. Find the maximum profit to the nearest dollar. p(x)=x2+50x+79

Answer 1

Hi,
Sorry, but there is no maximum to this profit function. It just keeps going and going the more videos that are rented. Besides, it's vertex is way over at x=-25.
To make a profit function of this with a maximum, you'd need something like this:
P(x) = -x² +50x +70
The you could either use the derivative or use the formula x=-b/2a.
Let's use the formula:
x=-b/(2a)
=-50/(2*(-1))
x=25
Now, plug that into the profit function:
P(25) =-(25²) +50*25 + 79
=-625+1250 +79
=704
If you somewho copied the wrong function, please post again with the correct function.

FE