Question

Does displacement = Δx?

Answer 1

Typically no. Displacement can be in multiple directions as a vector. of something is traveling only along x, then it would be true though this is usually not the case.

Answer 2

Displacement is the distance and direction from the start point to the end point.

If the motion starts and stops on the x-axis, then the displacement is equal to delta-x toward either the left or the right. But that would be rare and unusual.