Answer:
a) $50,880
b) $48
c) 1060
Step-by-step explanation:
a)
-320x^2 + 1920x + 48000 = 0
This is a parabola that opens downward. It has a maximum value. The maximum value occurs at x = -b/(2a)
x = -b/(2a) = (-1920)/(2(-320)) = 1920/640 = 3
The maximum revenue, y, is the value of the function evaluated at x = 3.
f(x) = -320x^2 + 1920x + 48000
f(-3) = -320(3)^2 + 1920(3) + 48000
f(-3) = 50,880
The maximum revenue is $50,880
b)
Since maximum revenue occurs at x = 3, and since x represents the number of $4 discounts, the discount is 3 * $4 = $12. The price is $60 - $12 = $48
c)
$50,880/$48 = 1060
.........Phitagors theory
First off, because the temperature is decreasing, that means the final answer would be negative, or we can also say that there would be a -1 to be multiplied by the change.
Each hour temperature changes by 7. The question also says that temperature keeps on changing for 3 hours. Therefore the temperature change would be by 3 7's, or 7+7+7.
Lastly, add the -1 from the beginning since it is a negative temperature change, the answer is (-1)(7+7+7)