How long does it take for a car to travel 400 m from a rest state with an acceleration of 2 m / s?

Moves from a state of rest v0 = 0 km / h, initial speed
Acceleration, a = 2 m / s ^ 2
S = 400 s distance traveled
To find how much time a car has spent, let’s use this formula:
S = v0 * t + (a * t ^ 2) / 2
v0 * t = 0, since the initial speed is 0 km / h
Let’s substitute the numbers in the formula:
400 = (2 * t ^ 2) / 2
Let’s transform:
800 = 2 * t ^ 2
400 = t ^ 2
t = √400
t = 20
Answer: it took the car 20 seconds