Answer:
A'(-2, -1), B'(0, 1), C'(-2, 0)
Explanation:
When dilation is about the origin, the scale factor multiplies each individual coordinate.
A' = (1/3)A = (-6/3, -3/3) = (-2, -1) . . . . for example
The rest is mental arithmetic, since all given coordinate values are divisible by 3.