If the point (x, y) is reflected across the x-axis, then its image is (x, -y)
If the point (x, y) is reflected across the y-axis, then its image is (-x, y)
Since triangle ABC is reflected across the x-axis, then across the y-axis, then we will change the signs of the x-coordinates and the y-coordinates of its vertices
A = (-5, -1), then
A' = (-5, 1)
A'' = (5, 1)
B = (-3, -5), then
B' = (-3, 5)
B'' = (3, 5)
C = (-1, -1), then
C' =(-1, 1)
C'' = (1, 1)