Parallel lines are straight lines which have the ... We've already seen that intersecting lines create vertically opposite angles that are equal. The lines make an X shape. Co-interior angles ...

Parallel lines are indicated by arrows going in the same direction. If there is more than one set of parallel lines in a diagram, different numbers of arrows are used. The three lines in this ...

with the other angle mirroring the opposite side. This example occurs when two parallel lines are intersected by a third straight line. With both parallel lines cut, the adjacent angles and ...