Two balanced three-phase systems, X and Y, are interconnected with lines having impedance \mathbf{Z}_{\text {line }}=1+j 2 \Omega. The line voltages are \mathbf{V}_{a b}=12 \underline{/ 0^{\circ}} \mathrm{kV} \mathrm{rms} and \mathbf{V}_{A B}=12 \underline{/ 5^{\circ}} \mathrm{kV} \mathrm{rms}, as shown in Fig. 11.22a. We wish to determine which system is the source, which is the load, and the average power supplied by the source and absorbed by the load.