1. Lesson 3.2 Use Parallel Lines and Transversals
Goal: The learner will use angles formed by parallel lines and transversals.

2. Draw a pair of parallel lines cut by a transversal.
Activity
Draw a pair of parallel lines cut by a transversal.
Trace your drawing on tracing paper.
Move the tracing paper so that 1 is over 5 of the original picture. Are they congruent?
Compare the eight angles and list the congruent pairs.
Click on Me for something cool.

3. Corresponding Angles Postulate
If two parallel lines are cut by a transversal, then corresponding angles are congruent.
Identify pairs of corresponding angles. Find the measures of all the angles.
120° 2 6 5 3 4 7 8

4. Alternate Interior Angles Theorem
If two parallel lines are cut by a transversal, then the alternate interior angles are congruent.

5. Alternate Exterior Angles Theorem
If two parallel lines are cut by a transversal, then the alternate exterior angles are congruent.

6. Consecutive Interior Angles Theorem
If two parallel lines are cut by a transversal, then the consecutive angles are supplementary.

7. Why are the angles congruent?60
120
115 60
100

8. Using Algebra and Properties
115
(x + 5)

9. 92
(2x -4)