1) The triangles are congruent by SSS.
The two tick marks indicate two pairs of congruent sides; it is evident that the third side is congruent by the way the diagram is drawn - the bases of the triangles are together and appear to be the same length.
2) The triangles are congruent by SAS.
The two pairs of tick marks indicate congruent sides, and their included angles are congruent because they are vertical angles, and vertical angles are always congruent.
Answer:
Inverse operations are opposite operations that undo each other. Addition and subtraction are inverse operations. Multiplication and division are inverse operations.
