Nodal Analysis of a circuit with a dependent source
Voltage at the node where R2 is connected is Vo, consider voltage at other node is \$V_1\$ By KCL:

$$\frac{V_o}{R_2} + \frac{V_o-V_1}{R_1} + \frac{V_o-V_2-2V_o}{R_3} = 0$$

To find \$V_2\$ here it is simply \$R_4 \cdot I_1 = 48V\$.

Now put the values and you will get your answer.

However you can do same using the loop analysis and KVL.

The thing is keep the dependent source variable as it is and just solve as you normally do.