# andand Angles 3-1 Lines Angles 3-1Lines Warm Up andand Angles 3-1 Lines Angles 3-1Lines Warm Up Lesson Presentation Lesson Quiz Holt McDougal

Geometry Geometry 3-1 Lines and Angles Warm Up Identify each of the following. 1. points that lie in the same plane coplanar points 2. two angles whose sum is 180 supplementary angles 3. the intersection of two distinct intersecting lines point 4. a pair of adjacent angles whose non-common

sides are opposite rays linear pair Holt McDougal Geometry 3-1 Lines and Angles Objectives Identify parallel, perpendicular, and skew lines. Identify the angles formed by two lines and a transversal.

Holt McDougal Geometry 3-1 Lines and Angles Vocabulary parallel lines perpendicular lines skew lines parallel planes transversal corresponding angles

alternate interior angles alternate exterior angles same-side interior angles Holt McDougal Geometry 3-1 Lines and Angles Holt McDougal Geometry 3-1 Lines and Angles Helpful Hint

Segments or rays are parallel, perpendicular, or skew if the lines that contain them are parallel, perpendicular, or skew. Holt McDougal Geometry 3-1 Lines and Angles Example 1: Identifying Types of Lines and Planes Identify each of the following. A. a pair of parallel segments

LM ||QR B. a pair of skew segments KN and PQ C. a pair of perpendicular segments NS SP D. a pair of parallel planes plane NMR || plane KLQ Holt McDougal Geometry 3-1 Lines and Angles Check It Out! Example 1 Identify each of the following.

a. a pair of parallel segments BF || EJ b. a pair of skew segments BF and DE are skew. c. a pair of perpendicular segments BF FJ d. a pair of parallel planes plane FJH || plane BCD Holt McDougal Geometry 3-1 Lines and Angles

Holt McDougal Geometry 3-1 Lines and Angles Example 2: Classifying Pairs of Angles Give an example of each angle pair. A. corresponding angles 1 and 5 B. alternate interior angles 3 and 5 C. alternate exterior angles 1 and 7 D. same-side interior angles

3 and 6 Holt McDougal Geometry 3-1 Lines and Angles Check It Out! Example 2 Give an example of each angle pair. A. corresponding angles 1 and 3 B. alternate interior angles 2 and 7 C. alternate exterior angles 1 and 8

D. same-side interior angles 2 and 3 Holt McDougal Geometry 3-1 Lines and Angles Helpful Hint To determine which line is the transversal for a given angle pair, locate the line that connects the vertices.

Holt McDougal Geometry 3-1 Lines and Angles Example 3: Identifying Angle Pairs and Transversals Identify the transversal and classify each angle pair. A. 1 and 3 transversal l corr. s B. 2 and 6 transversal n alt. int s

C. 4 and 6 transversal m alt. ext s Holt McDougal Geometry 3-1 Lines and Angles Check It Out! Example 3 Identify the transversal and classify the angle pair 2 and 5 in the diagram. transversal n same-side int. s.

Holt McDougal Geometry 3-1 Lines and Angles Lesson Quiz: Part I Identify each of the following. 1. a pair of parallel segments EH || FG 2. a pair of skew segments BF and EH 3. a pair of perpendicular segments CG GH

4. a pair of parallel planes ABC and EFG Holt McDougal Geometry 3-1 Lines and Angles Lesson Quiz: Part II Identify each of the following. 5. one pair alternate interior angles EHG and HGK 6. One pair corresponding angles

EHG and FGJ 7. one pair alternate exterior angles IHE and JGK 8. one pair same-side interior angles EHG and HGF Holt McDougal Geometry