Download presentation
Presentation is loading. Please wait.
Published byWillis Nelson Modified over 9 years ago
1
GOAL 1 PROVING LINES ARE PARALLEL The postulate and theorems learned in Section 3.3 all had the same hypothesis: Parallel lines are cut by a transversal. Now we will prove the converses to be true, and use them to prove lines are parallel. 3.4 Proving Lines are Parallel
2
POSTULATE Corresponding Angles Converse THEOREMS Alternate Interior Angles Converse Consecutive Interior Angles Converse Alternate Exterior Angles Converse EXAMPLE 1
3
Extra Example 1 EXAMPLE 2 1 2 m p q
4
Extra Example 2 EXAMPLE 3 AB CD 6 4 5
5
Extra Example 3 Find the value of x that makes mn
6
Checkpoint Given: are supplementary; are supplementary. Prove: cd j k 5 4 1
7
GOAL 2 USING THE PARALLEL CONVERSES EXAMPLE 4EXAMPLE 5 3.4 Proving Lines are Parallel
8
Extra Example 4 You notice that when your windshield wipers on your car stopped they each made a 30° angle with the bottom of the windshield. If the wipers were long enough, would they ever cross each other? Explain.
9
Extra Example 5 155° 65°40° 65° AB CD
10
Checkpoint 1. When lines r and s are cut by a transversal, are same side interior angles. If is three times, can line r be parallel to line s? Explain.
11
QUESTIONS?
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.