Answer:
∠1 and ∠2 are congruent because they are a pair of corresponding angles.
Explanation:
The position described is for corresponding angles: one in the upper right exterior corner and another in the upper right corner in the bottom line, one exterior to the parallels and the another one interior to the parallels; that specific position makes them congruent.
In addition, the specific characteristic to call these angles congruent, besides their position, it's that there have to be a pair of parallels intersected by a transversal. If it's not a parallel, those angles are not corresponding angles, and are not congruent.
(An image is attached)