If two shapes are congruent, which statement must be true?

• A. Corresponding angles are equal and corresponding sides are equal
• B. Only areas are equal
• C. Only perimeters are equal
• D. Only shapes are similar

Answer: (A)

Congruent shapes have the same size and shape, and you can map one onto the other with a rigid motion so every part lines up exactly. Because of that, every corresponding angle has the same measure and every corresponding side has the same length. That means the statement describing both equal angles and equal sides must be true.

This isn’t just about equal areas or equal perimeters, and it isn’t merely about similarity. Congruence means identical in size as well as shape, so the equal angles and equal sides capture the full relationship.