When a pair of parallel lines meet an intersecting transversal, pairs of angles with particular properties are made. Corresponding angles are equal. The lines make an F shape. Notice that the F ...

The diagonal line is a transversal as it is crossing the pair of parallel lines. When two lines intersect, the opposite angles are equal. Alternate angles are on opposite sides of the transversal ...

With both parallel lines cut, the adjacent angles and corresponding ... This theorem dictates that the supplementary angles of linear pairs are interchangeable between congruent figures.