a car is worth 24000 and it depreciates 3000 a year how long till it costs 9000

a car is worth 24000 and it depreciates 3000 a year how long till it costs 9000

Let y be the number of years. We want to know y when:
24000 - 3000y = 9000

Typing this equation into our search engine, we get:
y = 5