Parallel Lines and Transversals Lesson 3.1

Parallel lines – coplanar lines that never intersect. Parallel planes – planes that never intersect. Transversal – A line that intersects 2 or more other lines.

Consecutive interior angles – one after the other on the 1 2 3 4 Consecutive interior angles – one after the other on the same side of t inside the lines. (one on each line) Alternate interior angles – on opposite sides of t, inside the lines. (one on each line) 5 6 7 8 t Alternate exterior angles – on opposite sides of t, outside the lines. (one on each line) Corresponding angles – on the same side of t, in corresponding positions. (one on each line)

Skew Lines – lines that never intersect, are on different planes and are not parallel.