Two particles each of mass `m` and speed `v`, travel in opposite direction along parallel lines separated by a distance d. Show that the vector angular momentum of this system of particles is the same about any point taken as origin.

Explanation

To solve the problem, we need to calculate the angular momentum of two particles of mass `m` moving with speed `v` in opposite directions along parallel lines separated by a distance `d`. We will show that the vector angular momentum of this system is the same about any point taken as the origin.

### Step-by-Step Solution:

1. **Identify the System**:
- We have two particles, each of mass `m`.
- One particle moves in the positive direction along one line, and the other moves in the negative direction along a parallel line.

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