a.) (3,3) (3,9) (9,3)
b.) (0,0) (0,6) (6,0)
c.) (3,3) (0,9) (9,0)
d.) (0,0) (0,9) (9,0)

Explanation:

The original three vertices are A = (0,0), B = (0,3) and C = (3,0). Each point is formed by reading the columns from top to bottom.

Multiply those coordinates by 3

A = (0,0) turns into A ' = (0,0) ... ie there's no change here

B = (0,3) turns into B ' = (0, 9)

C = (3,0) turns into C ' = (9, 0)

The three points A', B', and C' are three times further away from the origin compared to the original points A, B, C.