What is Angle Pairs in Parallel Lines ?

Next, we introduce several angle pairs formed by transversals which are very important in our study of geometry.
Alternate interior angles
If two lines are cut by a transversal the two pairs of alternate interior angles are
3 and 6, 4 and 5.
The features for alternate interior angles are:
1. They are interior angles.
2. They are on opposite sides of the transversal.
3. They do not have the same vertex.

Alternate exterior angles
If two lines are cut by a transversal the two pairs of alternate exterior angles are 1 and 8, 2 and
The features for alternate exterior angles are:
1. Angles are exterior angles.
2. Angles are on opposite sides of the transversal.
3. Angles do not have the same vertex.

Corresponding angles
If two lines are cut by a transversal the four pais of corresponding angles are 1 and5, 2 and 6,3 and 7, 4 and 8
The features for corresponding angles are:
1. One angle is an interior angle; the other angle is an exterior angle.
2. Angles are on the same side of the transversal.
3. Angles do not have the same vertex.