Going off the given statement we have an angle and a side in each triangle that are congruent to each other. Since vertical angles are congruent, we have now 2 angles and a side, or more specifically, an angle then a side then an angle, which makes those triangles congruent by ASA. That's #3. If the triangles are already proven to be congruent, then anything else that's congrunet between the triangles is because CPCTC. That's #4.
