Lines And Angles

Lines and Angles g 3.1

Lines and Angles • Parallel lines – Coplanar li lines th thatt d do nott iintersect. t t

Lines and Angles • Skew lines – lines that do not i t intersect t and d are nott coplanar. cop a a

Parallel Postulate: If there is a line and a point not on the line, th there then th is i exactly tl one liline through the point parallel to the given line

Perpendicular Postulate: If there is a line and a point not on the th liline, th then th there iis exactly one line through the point perpendicular to the given line

Transversal a line that intersects two or more coplanar lines at different points.

Interior

Exterior

E t i Exterior

1 2 3 4 5 6 7 8 Corresponding angles

1 2 3 4 5 6 7 8 Alternate Exterior angles

1 2 3 4 5 6 7 8 Alternate Interior angles

1 2 3 4 5 6 7 8 Consecutive Interior angles