Question

A building contractor estimates that her profit in dollars for a tall building will be given by the function:

P (h) = -4h2 + 160h,
where h represents the numer of floors in the buliding.
What height will give the maximum profit? What is the maximum profit?
Question to answer: What is the maximum profit?
profit is———
dollars

Answer 1

The height is 20

The max profit is 1600

Explanation:

P (h) = -4h^2 + 160h

The vertex is at

-b/2a = -160/2(-4) = 160/8 = 20

The height that will give the maximum profit is 20

We want to find the value at 20

P(40) =-4(20)^2 +160(20)

=-1600+3200

1600