Answer:
SAS (side-angle-side)
Explanation:
In the given picture, it is shown that the triangles have two congruent sides, and one congruent angle between them. The congruent sides are shown by the lines on the sides. The congruent angle is shown by the box outlining the angle (technically a box outlining the angle demonstrates that the angle is a right angle, either way, it proves the congruency).