Answer:
The answer to your question is: -6m/s²
Explanation:
Data
vo = 30 m/s
vf = 12 m/s
t = 3 s
a = ?
Formula
vf = vo + at
a = (vt - vo) / t
Process
a = (12 - 30) / 3 substitution
a = -18 / 3 simplify
a = -6 m/s² result, is negative because the car
is slowing down.