Find nonadjacent interior angles that lie on the opposite sides of a transversal.
∠ 1 and ∠ 5
∠ 4 and ∠ 6
∠ 2 and ∠ 8
∠ 3 and ∠ 7
Practice makes perfect
Recall that alternate interior angles are nonadjacent interior angles that lie on opposite sides of a transversal. From the diagram we see that on the left side, ∠ 4 and ∠ 6 as well as ∠ 5 and ∠ 1 are alternate interior angles formed by l and m, and AC.
On the right side, ∠ 8 and ∠ 2 as well as ∠ 3 and ∠ 7 form pairs of alternate interior angles by l and m, and the transversal BD.
