Answer:
Step-by-step explanation:
The x intercepts are 0 and
1000 - 2x = 0 given condition
1000 = 2x Divide by 2
500 = x
So the two intercepts are 0,0 and 500,0
The intercepts mean that for (0,0) the phone company hasn't charged anything, yet. For 500,0 the phone company can sell a single phone -- not when they cost 500 dollars apiece.
The answer to the B part is completing the square.
r(x) = - 2x^2 + 1000x
r(x) = -2(x^2 - 500x )
1/2 ( 500) = 250
250^2 is what you put inside the bracket's to complete the square.
r(x) = - 2(x^2 - 500x + 250^2) + 2*250^2
r(x) = -2(x - 250)^2 + 2*62500
r(x) = - 2(x - 250)^2 + 125000
They should sell their phones at 250 dollars a piece. The total revenue is 125000. Your graph shows exactly the same thing.