- #1

- 39

- 0

I believe what I need to do is find the maximum vertex of the parabola in order to solve the equation. So I did the following:

R = -40c^2 - 720c

= -40(c^2 - 18c)

= -40(c^2 - 18c + 9^2 - 9^2) <-- complete the square

= -40(c^2 - 18c + 81 - 81)

= -40[(c^2 - 9)^2 - 81)

= -40(c^2 - 9)^2 + 3240

Which would give me a vertex (9, 3240) but this does not make sense to me, I am not sure what I am looking for to be honest. I believe that the maximum price would be $9.00 to have a revenue of $3240, is this correct and I am just second guessing?