What does it mean to prove that two figures are congruent using rigid motions?

Proving that two figures are congruent using rigid motions involves demonstrating that one figure can be transformed into the other through a series of translations, rotations, and reflections without changing the size or shape of the original figure. This proof relies on the principle that rigid motions preserve distance and angle measures. By showing that the corresponding parts of the two figures align perfectly after applying these transformations, it can be concluded that the figures are congruent.