Answer:
B
Step-by-step explanation:
So we have a table of values of a used car over time. At year 0, the car is worth $20,000. By the end of year 8, the car is only worth $3400.
We can see that this is exponential decay since each subsequent year the car depreciates by a different value.
To find the rate of change the car depreciates, we simply need to find the value of the exponential decay. To do this (and for the most accurate results) we can use the last term (8, 3400).
First, we already determined that the original value (year 0 value) of the car is 20,000. Therefore, we can say:
[tex]f(t)=20000(r)^t[/tex]
Where t is the time in years and r is the rate (what we're trying to figure out).
Now, to solve for r, use to point (8, 3400). Plug in 8 for t and 3400 for f(t):
[tex]3400=20000(r)^8\\3400/20000=17/100=r^8\\r=\sqrt[8]{17/100}\approx0.8[/tex]
In other words, the rate of change modeled by the function is 0.8.
As expected, this is exponential decay. The 0.8 tells us that the car depreciates by 20% per year.
