Answer:
Acceleration,

Step-by-step explanation:
It is given that,
Initial velocity of the car, u = 10 m/s (in right)
Final velocity of the car, v = -5 m/s (in left)
Time taken, t = 10 s
Let a is the acceleration of the car. It can be calculated using the equation of kinematics. The equation is as :



So, the acceleration of the car is
. Hence, this is the required solution.