Source and load impedances divide voltage only in the checked same-phase case. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Same-phase impedances form a checked divider
Source impedance 2 ohms and load impedance 6 ohms put 6 parts out of 8 on the load.
ZS+ZLZL=86
The load voltage follows the divider
Input 16 volts gives load voltage 12 volts and source drop 4 volts.