Exercise 1 Page 702

On the figure there is a line that is transversal to two other lines, a and b. We are also told that lines a and b are parallel.

There are several angle pairs on the diagram. Let's see if the angle pairs mentioned in the question are in a special position or not.

Let's see if we can quote a theorem that guarantees the congruence of the angles in each pair.

The Vertical Angles Theorem states that vertical angles are congruent. Thus, the statement in option A is true.
Since lines a and b are parallel, the Alternate Interior Angles Theorem states that alternate interior angles are congruent. Thus the statement in option B is true.
Since lines a and b are parallel, the Alternate Exterior Angles Theorem states that alternate exterior angles are congruent. Thus the statement in option C is true.

Since the statements in options A, B, and C are always true, the correct answer is option D. Angles ∠ 8 and ∠ 2 may not be congruent.