Mathematics for IGCSE & O level - Transformations (Section 4 - No. 15)
If a point is reflected over the line y=x, what is the rule?
(x,y) -> (-x, -y)
(x,y) -> (-y, x)
(x,y) -> (y, x)
(x,y) -> (x, -y)
Explicació
Reflection across y=x swaps the x and y values.