Question

A new car worth $27,000 is depreciating in value by $3,000 per year. After how many years will the car's value be $3,000?

Answer 1

The equation for the worth of car after x number of years is,

$\begin{gathered} y=27000-3000\cdot x \\ =27000-3000x \end{gathered}$

Substitute 3000 for y in the equation to obtain the value of x.

$\begin{gathered} 3000=27000-3000x \\ 3000x=27000-3000 \\ x=\frac{24000}{3000} \\ =8 \end{gathered}$

So after 8 years the worth of car is $3000.