Answer:
![[km^2]](https://tex.z-dn.net/?f=%5Bkm%5E2%5D)
Step-by-step explanation:
In this problem, the initial area of the forest at time t = 0 is

After every year, the area of the forest decreases by 9.8%: this means that the area of the forest every year is (100%-9.8%=90.2%) of the area of the previous year.
So for instance, after 1 year, the area is

After 2 years,

And so on. So, after t years, the area of the forest will be

And by substituting the value of A0, we can find an explicit expression:
![[km^2]](https://tex.z-dn.net/?f=%5Bkm%5E2%5D)
Answer:
the letter f isn't stated at all so f is a good choice
Step-by-step explanation:
Answer:
x ≈ 2.30277563
Step-by-step explanation:
One way to do this is to try the different option to replace x. Let's start with 8. Two sides of the rectangle would be 8.
8*2=16
Now you have to take 16 from 40 to see what's left.
40-16=24
2(20-8)=2(12)=24
That means 8 is an option to use, but you still need to see if any of the other options work to find the greatest area.
9*2=18.......40-18=22.......2(20-9)=2(11)=22
9 would also work.
10*2=20.......40-20=20.......2(20-10)=2(10)=20
10 would work
11*2=22.......40-22=18.......2(20-11)=2(9)=18
So all of them would work. Now you just need to find the largest area, which is length x width.
x(20-x)
8(20-8)=8(12)=96
9(20-9)=9(11)=99
10(20-10)=10(10)=100
11(20-11)=11(9)=99
So if x is 10, It would make the largest area.
(Sorry for all the extra work. I never trust that all the answers would work for the perimeter)