1. 3.2 Notes: Use Parallel Lines and Transversals
Goal: You will use angles formed by parallel lines and transversals.

2. your notes

3. Postulate 15 Corresponding Angles Postulate:
If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent.
Ex.1: The measure of three of the numbered angles is 120o. Identify the angles. Explain your reasoning.

4. Theorem 3.1 Alternate Interior Angles Thm:
If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent.
Theorem 3.2 Alternate Exterior Angles Thm:
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent.
Theorem 3.3 Consecutive Interior Angles Thm:
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary.

5. your notes

6. Ex: Use the diagram. a. If , find and Tell which postulate or theorem you used in each case. b. If and , what is the value of x? Show your steps.

7. Ex: Find the value of x.

8. your notes

9. your notes

10. Exit Questions:
Ex: Find the value of x and y.
Ex: Find and