Answer is (-2, -5) (-1, -5) ( -1, -8)
Step by step
the rule of reflection for y = -x
When reflecting over the line y=-x, we switch our x and y, and make both negative.
So these are the changes to new vertices
(5, 2) ➡️ (-2, -5)
(5, 1) ➡️ ( -1, -5)
(8, 1) ➡️ (-1, -8)