Exercise 7 Page 207

Alternate interior angles are nonadjacent interior angles that lie on the opposite sides of the transversal. We can examine the given diagram to try to find such pairs of angles.

The first pair of angles we can see is $\angle 2$ and $\angle 7.$ These are alternate interior angles formed by the lines $a$ and $b,$ and the transversal $d.$

Also, $\angle 3$ and $\angle 6$ are alternate interior angles. This pair is formed by the lines $c$ and $d,$ and the transversal $e.$

The last pair we can find is $\angle 3$ and $\angle 8.$ These are formed by the lines $b$ and $e,$ and the transversal $c.$