9514 1404 393
Answer:
2 -i
Step-by-step explanation:
The two diagonals have the same center point. Here, it is ...
(1 +2) +(-1 -2i) = 0 +0i
The fourth point is found by reflecting the 2nd point across the origin:
p4 = -p2 = -(-2 +i) = 2 -i . . . . . fourth corner of the square
