What is the solution?

1) x = 30 - 8 t

2) x = -10

3) x = -10 + 5 t

4) x = -10 - 4 t

Explanation:

Motion 1:  constant negative velocity calculated via the points (0, 30) and (5, -10) rendering the equation of motion  x = 30 - 8 t

Motion 2: constant position over time, so the object is not moving, and the equation of motion is x = -10

Motion 3: constant positive velocity estimated via the points (0, -10) and (2, 0), and the equation of motion is:  x = -10 + 5 t

Motion 4: constant negative velocity estimated via the points (0, -10) and (5, -30), and the equation of motion is:  x = -10 - 4 t

The starting position of motion 1 is 30 meters

the starting position for the other 3 motions is - 10 meters. And none of them is accelerated (acceleration = zero for all).