Step 1 :The initial value of the SUV is given as \(V_{0} = \$ 31,500\).
Step 2 :The vehicle is depreciated so that it holds only \(90 \%\) of its value from the previous year. This means the base of the exponential function, \(b\), is \(0.90\).
Step 3 :Therefore, the exponential function that models the value of the vehicle \(t\) years after purchase is: \[y=V_{0} b^{t} = 31500(0.90)^{t}\]
Step 4 :Final Answer: The model for the value of the vehicle \(t\) years after purchase is \(\boxed{y=31500(0.90)^{t}}\).