1. Chapter 3
Section 3.1 & 3.2 Identify pairs of lines and angles and use parallel lines with transversals
Objective:
SWBAT identify angle pairs formed by three intersecting lines, and use angles formed by parallel lines and transversals.

2. Parallel Lines
Lines that
do not
Intersect
and are
coplanar

3. Parallel Planes
Planes that
Do not
Intersect

4. Skew Lines
Lines that do
Not intersect
and are not
Coplanar.

5. Ex. 1: Identify Relationships in Space
Think of each segment in the figure as part of a line. Which line(s) or plane(s) in the figure appear to fit the description?

6. Some More Postulates Parallel Postulate:
If there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line.

7. Some More Postulates 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.

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

9. Vocabulary
4 types of angles formed by a transversal:

10. Vocabulary

11. Classify the angle pairx y

12. Classify the angle pairm n

13. Classify the angle pairq

14. More Postulates and Theorems
Corresponding Angles Postulate
If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent

15. More Postulates and Theorems
Alternate Interior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of alternate interior angles and congruent.

16. More Postulates and Theorems
Alternate Exterior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent.

17. More Postulates and Theorems
Consecutive Interior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary.

18. Solve for the variable 2p
120

19. Solve for the variable x 80

20. Find all the missing angle measures
105

21. Solve for x and the measure of angle 4.

22. Example: Use the diagram.
If m = 68° and m = (2x + 4)°, what is the value of x? Show your steps.

23. Homework Textbook pg. 142 Textbook pg. 149 # 4, 6, 18, 20, 22
# 4, 6, 8, 17, 19