Answer:
y= 6971 -7 x OR y = -7x + 6971
Step-by-step explanation:
the 6971 is the original number you started with, you are now decreasing by 7, so you use the value of -7. The x is the number of years that pass by, so the variable x affects the number 7 because it says decreases by 7 per year. The x does not go with 6971 as that number doesn't get directly affected.
Answer:

Step-by-step explanation:
-We can use the exponential decay function to estimate the size after 13 years:

Where:
is the size after t years, t is the time, r is the rate of decay and
the original size.
#We substitute and calculate as:

Hence, the forest covers
after 13 years.
Answer:
(p-2l)/2 = w
Step-by-step explanation:
p=2l+2w
We want to solve for w.
The first step is to subtract 2l from each side
p-2l=2l-2l+2w
p-2l=2w
Then we will divide each side by 2 to isolate w
(p-2l)/2 = 2w/2
(p-2l)/2 = w