A) Demand function
price (x) demand (D(x))
4 540
3.50 810
D - 540 810 - 540
----------- = -----------------
x - 4 3.50 - 4
D - 540
----------- = - 540
x - 4
D - 540 = - 540(x - 4)
D = -540x + 2160 + 540
D = 2700 - 540x
D(x) = 2700 - 540x
Revenue function, R(x)
R(x) = price * demand = x * D(x)
R(x) = x* (2700 - 540x) = 2700x - 540x^2
b) Profit, P(x)
profit = revenue - cost
P(x) = R(x) - 30
P(x) = [2700x - 540x^2] - 30
P(x) = 2700x - 540x^2 - 30
Largest possible profit => vertex of the parabola
vertex of 2700x - 540x^2 - 30
When you calculate the vertex you find x = 5 /2
=> P(x) = 3345
Answer: you should charge a log-on fee of $2.5 to have the largest profit, which is $3345.
Answer: 918km^2
Step-by-step explanation:

Let x be the new dimension of the area;


Answer:
39°
Step-by-step explanation:
51° +? = 90°
? = 90° - 51°
? = 39°
Hope it helps you in your learning process.
The choices are <span><span> A. r= 200 over w; r = 40 B. r = 200 over w; C. r = 1000
C. r = 2w; r = 10 D. r = 2w; r = 2.5. T</span>he situation</span> implies that the number of roses is inversely proportional to the number of weeds. In this case, the answer is either a or b. Given 5 weeds,the one that fits is A. <span>A. r= 200 over w; r = 40. </span>