DO NOW: 1. Write as a biconditional: If it is an egg then it is green. 2.

3.1 Pairs of Lines and Angles OBJ: The student will be able to identify lines, planes, parallel liens, perpendicular, and pairs of angles formed by transversal.

Definitions Parallel Lines: two lines that do not intersect and are coplanar. Skew Lines: two lines that do not intersect and are not coplanar. Parallel Planes: two planes that do not intersect

Ex. 1

Postulate 3.1 Parallel Postulate: If there is a line and a point not on the line, then there exists exactly one line through the point parallel to the given line. There is exactly one line through P parallel to l.

Postulate 3.2 Perpendicular Postulate: If there is a line and a point not on the line, then there is exactly one line through the point perpendicular to the given line. There is exactly one line through P perpendicular to l.

Ex. 2

Transversals Transversal: a line that intersects two or more coplanar lines at different points There are 4 types of angles formed by transversals: corresponding, alternate interior, alternate exterior, and consecutive interior angles.

Corresponding Angles: two angles that have corresponding positions.

Alternate Interior Angles: two angles that lie between the two lines on opposite sides of the transversal.

Alternate Exterior Angles: two angles that lie outside the two lines and on opposite sides of the transversal.

Consecutive Interior Angles: two angles that lie between the two lines and on the same side of the transversal.

Ex. 3

HW: Pg , 24 a-c