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

To prove that two triangles with three congruent, corresponding angles are congruent, you would need to have at least one set of corresponding sides that are also congruent. You could then use ASA or AAS congruence theorems or rigid transformations to prove congruence.

Step-by-step explanation:

Step-by-step explanation:

I feature of congruence of triangles: side-side-side

Available two triangles must match equal sides, these triangles are congruent.

II feature of congruence of triangles side - angle - side

Available two sides and the angle contained between them in one triangle are equal to two sides and the angle contained between them in the other triangle, these triangles are congruent.

III feature of congruence of triangles angle - side - angle

If the side and two adjacent angles in one triangle, they are equal to the side and two adjacent angles of the other triangle, these triangles are congruent.

The first feature of congruence of triangles is side-side-side (SSS). In SSS, two triangles must match equal sides. These triangles are congruent. The second feature of congruence of triangles is side - angle - side (SAS). In SAS, two sides and the angle contained between them in one triangle are equal to two sides and the angle contained between them in the other triangle. These triangles are also congruent. The third feature of congruence of triangles is angle - side - angle (ASA). In ASA, if the side and two adjacent angles in one triangle, they are equal to the side and the two adjacent angles of the other triangle. These triangles are congruent as well.

Explanation: Correct on Edg 2020