Finding value of Vo in a circuit
Name the meshes a,b,c,d for left, top, right, bottom, respectivly:

Becuase of the two current sources:

Ia = 2mA

Ic - Id = 2mA

We also can do KVL for 3 circuits that don't involve current source:

Vo + (Ib-Id)*1k - 2Vx = 0

Vo + (Ib-Id)*1k + Vx -4V - Ic*1k = 0

2Vx + Vx -4 - Ic*1k = 0

Two resistors are given voltage labels and sizes and we know mess current:

Vo = 1k*(Ib - Ic)

Vx = 1k*(Ia - Id)

Now it is simply a matter of solving the simultaneous equations. Which results in:

Ia = 2mA, Ib = 3mA, Ic = 2mA, Id = 0mA, Vo = 1V, Vx = 2V.