Answer: 45,000.
Step-by-step explanation:
The equation of inverse variation is given by:-
, where k is the constant of proportionality.
Given: After owning the car for 3 years, its value is $15,000. After owning the car for 5 years, its value is $9,000.
Here,
Then,
or [answer is same in both cases.]
Hence, the constant of proportionality in this inverse variation is 45,000.