Answer:
A 90 degrees counterclockwise rotation about the origin followed by a translation 1 unit to the left
Explanation:
The transformation of coordinates for figure ABCD ⇒ A'B'C'D' is ...
(x, y) ⇒ (-y-1, x)
__
We know the transformation ...
(x, y) ⇒ (-y, x)
represents a CCW rotation by 90°. And the transformation ...
(x, y) ⇒ (x-1, y)
represents a translation 1 unit left.
Combined, the rotation and translation produce the transformation described above. This figure has undergone ...
a 90° CCW rotation about the origin, followed by a translation 1 unit left.