[list][br][*]Two parallel lines are intersected by a transversal line, producing 8 angles.[br][/*][*]Observe the angle pairs: [b]Corresponding, Vertical, Alternate Interior, Alternate Exterior, Same Side Interior,[/b] and [b]Same Side Exterior[/b].[/*][*]Observe whether the angle pairs are congruent or supplementary.[/*][*]Use [b]Parallel Lines[/b] checkbox to force parallel lines[br][br][/*][/list]