Each pair of triangles are congruent. The congruence reasoning is shown below.
ASA
SSS
HA
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Further Explanation:
ASA is where we have the marked side between two marked angles. This is slightly different from AAS or SAA. The order is important. The diagram shows how the angles pair up (eg: the double arc angles are the same measure). Using ASA is enough to prove the triangles congruent.
SSS is used here because we have three pairs of congruent sides. The unmarked sides overlap perfectly, so we consider this a shared side. They are congruent to each other (because of the reflexive property). So we have enough info to show that the triangles are congruent.
HA stands for hypotenuse angle. It's probably not that often used. It only applies to right triangles. The two overlapped segments are the hypotenuse of each right triangle, so that takes care of the "H" of "HA". The A part refers to the congruent acute angles (not the right angles). Therefore, the triangles are congruent by the HA theorem.
