18.
To model this situation, we can use an exponential equation:
[tex]y=a\cdot(1+r)^t[/tex]Where a is the initial value, t is the time in years and r is the rate of increase or decrease.
So for this case, we have a = 25000 and r = -0.35 (negative because the value decreases each year).
Therefore the equation is:
[tex]\begin{gathered} y=25000\cdot(1-0.35)^t \\ y=25000(0.65)^t \end{gathered}[/tex]19.
After 3 years (that is, for t = 3), the price of the vehicle will be:
[tex]\begin{gathered} y=25000(0.65)^3 \\ y=25000\cdot0.274625 \\ y=6865.62 \end{gathered}[/tex]The price will be $6,865.62.