The diagram is attached with the answer to explain the scenario.
We can see that ∠1 and ∠2 are supplementary angles i.e. their sum will be 180°
So,
m∠1 + m∠2 = 180°
61.8° + m∠2 = 180°
m∠2 = 180° - 61.8°
m∠2 = 118.2°
Corresponding angles are those angles which have the same relative position on each intersection where a line intersects two other lines. If the two other lines are parallel then corresponding angles are equal.
We can see from the diagram that ∠2 and ∠6 have the same realtive position and as the lines which were intersected are parallel so