You have the coordinates for triangle ABC
A (2,1)
B (6,1)
C (4,4)
To perform a reflection over the x-axis, the x-coordinarte remains the same and you have to invert the sing of the y-coordinate, for example for a point P(x,y):
Preimage → Image
P(x,y) → P'(x,-y)
So to reflect triangle ABC to triangle A'B'C' you have to do as follows:
A (2,1) → A'(2,-1)
B (6,1) → B'(6,-1)
C (4,4) → C'(4,-4)
