Final answer:
A coordinate of (20, -55) in GIS would be located in the Western hemisphere and south of the equator.
Step-by-step explanation:
A coordinate of (20, -55) in the Geographic Information System (GIS) would be located in the Western hemisphere and south of the equator. This is because the positive x-coordinate represents the east of the prime meridian, and the positive y-coordinate represents the north of the equator. Therefore, since the x-coordinate is positive and the y-coordinate is negative, the point is located in the West and South of the prime meridian and equator respectively.