Lines BC and AD are parallel as well as lines AB and CD.
Work Step by Step
If angle 1 and angle 2 are congruent, that makes them alternate interior angles for both of these pairs of parallel lines.
You can help us out by revising, improving and updating this answer.Update this answer
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.