Using alternate exterior angles to shown when two lines are parallel

The video tutorial explains how to determine if two angles are parallel by using the concept of alternate exterior angles. It introduces the theorem that states when alternate exterior angles are equal, the lines are parallel. The tutorial demonstrates solving for the variable X to make the angles equal, thus proving the lines are parallel.

What is the significance of finding that X equals 45 in the context of the angles discussed?

Describe the relationship between equal alternate exterior angles and parallel lines.