What else would need to be congruent to show that abc~xyz by asa? given: ab~xy, a~x,

Two triangles are said to be congruent by ASA congrency criterion if the two angles and side between them are equal or congruent.

Refer to the image attached.

To prove:

Given:

Now, we can observe that the side AB is between the angles A and B and the side XY is between the angles X and Y.

Since it is given that  , so the condition should be known to shows these triangles congruent.