Original solution

Solution added

Superposed solution

1

(u₁, v₁, 0)

(u₂, v₂, 0)

(u₁+ u₂, v₁+ v₂, 0)

2

(u, v, 0)

(0, 0, w)

(u, v, w)

3

(u₁, 0, u₂)

(0, u₀, 0)

(u₁, u₀, u₂)

4

(0, u₀, 0)

(u₁, 0, u₂)

(u₁, u₀, u₂)