1. 7-4 Classifying Lines Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day

2. Warm Up Give the complement and supplement of each angle. 1. 80° 2. 64° 3. 15° 10°, 100° 26°, 116° 75°, 165° Course 1 7-4 Classifying Lines

3. Problem of the Day Draw three points that are not in a straight line. Label them A, B, and C. How many different lines can you draw that contains two of the points? Name the lines. Course 1 7-4 Classifying Lines 3; AB, AC, BC

4. Learn to classify the different types of lines. Course 1 7-4 Classifying Lines

5. Vocabulary parallel lines perpendicular lines skew lines Insert Lesson Title Here Course 1 7-4 Classifying Lines

6. Course 1 7-4 Classifying Lines Intersecting lines are lines that cross at one common point. Parallel lines are lines in the same plane that never intersect. Line YZ intersects line WX. YZ intersects WX. Line AB is parallel to line ML. AB ML. Y W Z X B A M L

7. Course 1 7-4 Classifying Lines Perpendicular lines intersect to form 90° angles, or right angles. Line RS is perpendicular to line TU. RS TU. S R TU The square inside a right angle shows that the rays of the angle are perpendicular. Writing Math

8. Course 1 7-4 Classifying Lines Skew lines are lines that lie in different planes. They are neither parallel nor intersecting. Line AB and line ML are skew. AB and ML are skew. M L A B

9. Course 1 7-4 Classifying Lines Additional Example 1A: Classifying Pairs of Lines Classify each pair of lines. A. The lines intersect to form right angles. They are perpendicular.

10. Course 1 7-4 Classifying Lines Additional Example 1B: Classifying Pairs of Lines Classify each pair of lines. B. The lines are in different planes and are not parallel or intersecting. They are skew.

11. Course 1 7-4 Classifying Lines Additional Example 1C: Classifying Pairs of Lines Classify each pair of lines. C. The lines are in the same plane. They do not appear to intersect. They are parallel.

12. Course 1 7-4 Classifying Lines Additional Example 1D: Classifying Pairs of Lines Classify each pair of lines. D. The lines cross at one common point. They are intersecting.

13. Course 1 7-4 Classifying Lines Try This: Example 1A Classify each pair of lines. A. The lines are in the same plane. They do not appear to intersect. They are parallel.

14. Course 1 7-4 Classifying Lines Try This: Example 1B Classify each pair of lines. B. The lines intersect to form right angles. They are perpendicular.

15. Course 1 7-4 Classifying Lines Try This: Additional Example 1C Classify each pair of lines. C. The lines are in different planes and are not parallel or intersecting. They are skew.

16. Course 1 7-4 Classifying Lines Try This: Additional Example 1D Classify each pair of lines. D. The lines cross at one common point. They are intersecting.

17. Course 1 7-4 Classifying Lines Additional Example 2: Application The handrails on an escalator are in the same plane. What type of line relationship do they represent? The handrails are in the same plane and do not intersect. The lines are parallel.

18. Course 1 7-4 Classifying Lines Try This: Example 2 The roads are in the same plane. What type of line relationship do they represent? The lines cross at one common point. The lines are intersecting.

19. Lesson Quiz 1. Sketch a pair of perpendicular lines. 2. Sketch a pair of parallel lines. Use the figure to classify the lines. 3. AD and BC 4. AD and CF 5. AB and BG parallel Insert Lesson Title Here skew perpendicular Course 1 7-4 Classifying Lines