1. Chapter 3: Parallel and Perpendicular Lines
Lesson 1: Parallel Lines and Transversals

2. Definitions
Parallel lines ( || )- coplanar lines that do not intersect (arrows on lines indicate which sets are parallel to each other)
Parallel planes two or more planes that do not intersect
Skew lines lines that do not intersect but are not parallel (are not coplanar)
Transversal a line that intersects two or more lines in a plane at different points

3. Pairs of angles formed by 2 lines and a transversal
Exterior angles : angles that are outside the two parallel lines
Interior angles: angles that are between the two parallel lines
Consecutive Interior angles: between the two parallel lines, on the same side of the transversal
Consecutive Exterior angles: outside the two parallel lines, on the same side of the transversal
Alternate Exterior angles: outside the two parallel lines, on different sides of the transversal
Alternate Interior angles: between the two parallel lines, on different sides of the transversal
Corresponding angles: one outside the parallel lines, one inside the parallel lines and both on the same side of the transversal

4. Examples A. Name all segments parallel to BC.
B. Name a segment skew to EH.
C. Name a plane parallel to plane ABG.

5. Examples
Classify the relationship between each set of angles as alternate interior, alternate exterior, corresponding, or consecutive interior angles
A. 2 and 6
B. 1 and 7
C. 3 and 8
D. 3 and 5

6. Examples
A. Identify the sets of lines to which line a is a transversal.
B. Identify the sets of lines to which line b is a transversal.
C. Identify the sets of lines to which line c is a transversal.