The resale value of a used vehicle is given by the formula V-Cl-r), where V dollars is the resale value, C dollars is the original price, ris the rate of depreciation as a decimal, and n is the age of the vehicle.

a) If a vehicle depreciates at a rate of 20% per year and the original price of the vehicle was $36,000, write a simplified exponential equation that can be used to determine the age of the vehicle. [2 marks]

b) Using the equation from part a) above, determine the age of the vehicle if its resale value aftern years is $8440.87. Show all of your work. [2 marks]