The reflection of any point across the x axis is the symmetric of this point, having x axis as axe of symmetry
Let :
A(1,3) its symmetric vs. x axis is A'(1,-3)
B(-1,5) its symmetric vs. x axis is B'(-1,-5)
C(-3,-3) its symmetric vs. x axis is C'(-3,3)
D(-4,-4) its symmetric vs. x axis is D'(-4,4)
Symmetry vs. the x axis keeps abscises the same & change just the sign of y value
