Two angles are congruent if they have the same measure. Two circles are congruent if they have the same diameter.

How can 2 angles be congruent?

Two angles are congruent if they have the same measure. You already know that when two lines intersect the vertical angles formed are congruent. ... When you expose these angle relationships, you will establish their truth using a formal proof.

Which angles are congruent?

Two angles are said to be congruent if their corresponding sides and angles are of equal measure. Two angles are also congruent if they coincide when superimposed. That is, if by turning it and/or moving it, they coincide with each other. The diagonals of a parallelogram also set up congruent vertex angles.