**Calculating the initial velocity of the car**

To calculate the initial velocity of the car, we need to use the equation of motion:

v = u + at

Here,
v = final velocity (0 m/s, as the car comes to a stop)
u = initial velocity (unknown)
a = acceleration (-20 m/s²)
t = time taken to stop (2 seconds)

**Substituting the values into the equation**

0 = u + (-20) * 2

Simplifying the equation, we have:

0 = u - 40

**Solving for the initial velocity**

To solve for the initial velocity, we need to isolate u on one side of the equation. By adding 40 to both sides of the equation, we get:

40 = u

Therefore, the initial velocity (u) of the car was 40 m/s.

**Explanation**

The given information states that the car has an acceleration of -20 m/s². The negative sign indicates that the car is decelerating or slowing down. This negative acceleration is caused by the application of brakes.

The problem also states that the car takes 2 seconds to stop after the application of brakes. This can be interpreted as the time it takes for the car to go from its initial velocity to a final velocity of 0 m/s (as it comes to a stop).

Using the equation of motion v = u + at, we substitute the given values. The final velocity is 0 m/s, the acceleration is -20 m/s², and the time is 2 seconds. Solving for the initial velocity (u), we find that it was 40 m/s.

Therefore, the car was traveling at an initial velocity of 40 m/s before the application of brakes.

40m/s