Answer: f(x) = -0.016x² + 1.6x
Step-by-step explanation:
If the lenght of the road over the arch is 100m, we can consider a coordinate plane and say that the road starts at point (0,0) and finishes at (100,0). The vertice of the parabola is at point (50,40), because the maximum height is 40 and it is always in the middle point of the roots.
So, we have
(0,0) (50,40) (100,0)
A quadratic function is always on the form: f(x) = ax² + bx + c
0 = a0² + b0 + c
40 = a50² + b50 + c
0 = a100² + b100 + c
0 = a0² + b0 + c → c = 0 ∴
40 = a50² + b50
0 = a100² + b100
_________________________
2500a + 50b = 40 (*2)
10000a + 100b = 0
_________________________
5000a + 100b = 80
10000a + 100b = 0 (-)
__________________________
-5000a = 80
-a=80/5000
a=-0.016
∴
2500a + 50b = 40
2500.(-0.016) + 50b = 40
-40 + 50b = 40
50b = 80
b = 80/50
b = 1.6
This way f(x) = -0.016x² + 1.6x
Answer:
8s-8
Step-by-step explanation:
Use the distributive property: #(a-b) = #*a - #*b. In this case 8s - 8.
Hope it helps!
There aren't really any instructions for this, so I'll just go ahead and find the total amount of money for both months. The first month Adriano had 200 subscribers. 5 times 200 is 1000, so Adriano received $1000 that month. The second month 40 members joined, but 10 cancelled their subscription. Taking this into account, we'll just say that 30 members joined. 30 times 5 is 150, and 150 plus 1000 is 1150. Therefore, Adriano had to have received $1150 the second month.
I'm not entirely sure what the question was to begin with, but I hope this answers it!
