last question needed for mastery please help thank you!

In 2010, a car was purchased for
$30,000. Each year since, the resale value has decreased by 24%.
Let t be the number of years since 2010. Let y be the value of the car, in dollars.
Write an exponential function showing the relationship between y and t.

Respuesta :

A= P(1+r)^t, where P= initial value, r= interest rate in %, and t = number of years.
However, if there isa decrease in value, the formula becomes:

A= P(1-r)^t and in our case :

A = 30,000(1- 0.24)^t  OR A = 30,000(0.76)^t