Parallel & Perpendicular Lines (Geometry - Unit 3)

What types of angles get formed when lines cross each other? Being able to recognize this is such an important skill. This unit will help you show your students how to recognize these important relationships and apply them in several scenarios including how they can be used in proofs.

This is a GROWING unit bundle that currently contains presentation notes, student follow-along notes handouts, glossary, glossary cards, 4 section quizzes, a study guide, and a unit test. Other items will be added over time, and the price will be modified as necessary during this process.

This is also one of the units that will be part of my complete Geometry curriculum that is currently in the works so keep checking back, and it will also work as a supplement to your current materials.

I am and have been a high school Geometry teacher for 20+ years, and all of the content has been used in my classroom.

The notes introduce each concept along with a few examples. They are in-depth enough to cover a topic well, and, at the same time, are brief enough to allow you to add related topics/examples of your choice without being overwhelming or stifling your own creativity/flexibility.

The topics included are:
1) Angle Pairs with Transversals
including corresponding, same-side interior, same-side exterior, alternate interior, and alternate exterior
2) Parallel Lines with Transversals
including how to use parallelism to determine angle sizes and how to use angle sizes to determine parallelism
3) Relating Parallel/Perpendicular Lines & Triangles
including auxiliary lines, the perpendicular transversal theorem, the triangle angle-sum theorem, the triangle exterior angle theorem, slopes of lines, and ratios of angles within a triangle
4) Vocabulary
16 terms along with 16 theorems/postulates

The preview contains a sampling of the notes and assessments.

Related Units
Geometry Basics: Introducing Points, Lines, Planes, & Angles (Geometry - Unit 1)
Reasoning & Proof: Using Logic (Geometry - Unit 2)

Full Curriculum Coming Soon!!

**This purchase is for one license only.**
If you are interested in purchasing multiple site licenses for a grade/department, school, or district, contact me at Please protect the proprietary nature of this product. It should not be made available to others without purchasing the license.

If you have any questions or requests, feel free to email me at

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About this resource


Created: Nov 28, 2016

Updated: Feb 22, 2018

Lesson Plan

zip, 3 MB


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