Question

in which figure do ∠1 and ∠2 represent a pair of alternate exterior angles?

Explanation:

Alternate exterior angles lie outside the two parallel lines, on opposite sides of the transversal, and are non-adjacent. We check each figure:

1. Top-left: ∠1 and ∠2 are on the same side of the transversal, not alternate exterior.
2. Top-right: ∠1 and ∠2 are inside the parallel lines, not exterior.
3. Bottom-left: ∠1 and ∠2 are on the same side of the transversal, not alternate exterior.
4. Bottom-right: ∠1 and ∠2 are outside the two parallel lines, on opposite sides of the transversal, fitting the definition of alternate exterior angles.

Answer:

The bottom-right figure (the fourth figure, with ∠1 above the top parallel line on the right of the transversal, ∠2 below the bottom parallel line on the left of the transversal) is the one where ∠1 and ∠2 are alternate exterior angles.