Angle Relationship theorems

Alternate Exterior Angles Converse Theorem

If two lines are cut by a transversal so that alternate exterior angles are congruent, then the lines are parallel.

Consecutive Interior Angles Theorem

If two lines are cut by a transversal so that consecutive interior angles are supplementary, then the lines are parallel

Converse of the Corresponding Angles Postulate

If two lines are cut by a transversal so that corresponding angles are congruent, then the lines are parallel.

Consecutive Exterior Angles Converse Theorem

If two lines are cut by a transversal so that each pair of consecutive exterior angles are supplementary, then the lines are parallel

Alternate Interior Angles Converse Theorem

If two lines are cut by a transversal so the alternate interior angles are congruent, then the lines are parallel.

Alternate Interior Angles Theorem

If two lines are parallel, then each pair of alternate interior angles are congruent

Alternate Exterior Angles Theorem

If two parallel lines are cut by a transversal, then each pair of alternate exterior angles are congruent

Consecutive Exterior Angles Theorem

If two parallel lines are cut by a transversal, then each pair of consecutive exterior angles are supplementary

Consecutive Interior Angles Theorem

If two parallel lines are cut by a transversal, then each pair of consecutive interior angles are supplementary.

Corresponding Angles Postulate

If two parallel lines are cut by a transversal, then each pair of corresponding angles is congruent.