Objectives
 Define skew and parallel lines.
 Use the correct notation to indicate parallel lines.
 Use the special angle relationships created by transversals and parallel lines to determine angle measures for corresponding angles, alternate interior angles, and consecutive angles.
Key Terms
 Alternate Interior Angles – two angles formed by a line (called a transversal) that intersects two parallel lines. The angles are on opposite sides of the transversal and inside the parallel lines.
 Angle of Incidence – the angle between a ray of light meeting a surface and the line perpendicular to the surface at the point of contact.
 Angle of Reflection – the angle between a ray of light reflecting off a surface and the line perpendicular to the surface at the point of contact.
 Consecutive Interior Angles – two angles formed by a line (called a transversal) that intersects two parallel lines. The angles are on the same side of the transversal and are inside the parallel lines.
 Corresponding Angles – two nonadjacent angles formed on the same side (same place) of a line (called a transversal) that intersects two parallel lines, with one angle interior and one angle exterior to the lines.
 Intersect – to cross over one another.
 Law of Reflection – a law stating that the angle of incidence is congruent to the angle of reflection.
 Parallel Lines – lines lying in the same plane without intersecting. Two or more lines are parallel if they lie in the same plane and do not intersect. Notation: the symbol  means “parallel.” If parallel lines are graphed on a Cartesian coordinate system, they have the same slope.
 Skew Lines – lines that are not in the same plane. Skew lines do not intersect, and they are not parallel.
 Transversal – a line, ray, or segment that intersects two or more coplanar lines, rays, or segments at different points.
Notes
Parallel Lines 


Skew Lines 


Transversals 






Law of Reflection 

