if two triangles have three congruent, corresponding
angles, what additional information is needed to prove
that the triangles are congruent?

Its needed to know that the length of the sides are the same.

If the angles are congruent that doesn’t mean the triangles are the same size.

So tringle A could have sides 3,3,and 3 and triangle B could have sides 6,6,and 6

In that case both triangles have congruent angles but not congruent size.

This mean that the triangles are similar but not congruent.

Brainliest my answer if it helps you out?