Consider the electrical circuit shown in Fig 3 Figure 3 The
     Consider the electrical circuit shown in Fig. 3.  Figure 3: The circuit of Problem 3  Find the Thevenin equivalent circuit between the terminals A and B.  Use the obtained result to calculate the current flowing in the Load resistor R_L in the sense A to B. 
  
  Solution
According to thevenian thorem any complex network can be reduced as a voltage source in SERIES with equivalent impedance.
Please follow below attachment to find required calculations

