1 / 10

Proving Parallel Lines Theorems | Geometry Postulates & Theorem | Line Relationships

Learn about the postulates and theorems that help prove lines are parallel in geometry. Understand the conditions for corresponding angles, alternate exterior angles, and more. Discover ways to prove lines parallel and enjoy some lighthearted jokes!

sdick
Download Presentation

Proving Parallel Lines Theorems | Geometry Postulates & Theorem | Line Relationships

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Proving Lines Parallel Section 3-5

  2. Postulate 3.4 • If 2 lines are cut by a transversal so that corresponding angles are congruent, then the lines are parallel. 60 60

  3. Parallel Line Theorems (3.5-3.8) • If 2 lines in a plane are cut by a transversal so that a pair of alternate exterior angles is congruent, then the lines are parallel. • If 2 lines in a plane are cut by a transversal so that a pair of consecutive interior angles is supplementary, then the lines are parallel. • If 2 lines in a plane are cut by a transversal so that a pair of alternate interior angles is congruent, then the lines are parallel.

  4. In a plane, if 2 lines are perpendicular to the same line, then they are parallel.

  5. Postulates • Through a point outside a line, there is exactly one line parallel to the given line. • Through a point outside a line, there is exactly one line perpendicular ot the given line.

  6. Theorem • 2 lines parallel to a 3rd line are parallel to each other.

  7. Ways to Prove 2 Lines Parallel • Show that a pair of corresponding angles are congruent. • Show that a pair of alternate interior angles are congruent. • Show that a pair of alternate exterior angles are congruent. • Show that a pair of consecutive interior angles are supplementary.

  8. In a plane, show that both lines are perpendicular to a 3rd line. • Show that both lines are parallel to a 3rd line.

  9. Joke Time How do you know when it’s raining cats and dogs? When you step in a poodle!

  10. Why did the apple go out with a fig? Because it couldn’t find a date

More Related