What are 3 rigid transformations that maintain congruence?

The three rigid transformations that maintain congruence are translations, rotations, and reflections. Translations slide a figure from one position to another without changing its shape or size. Rotations turn a figure around a fixed point, while reflections flip it over a line, creating a mirror image. All these transformations preserve the distances and angles, ensuring that the original and transformed figures remain congruent.