Ch 8: Big Ideas Math Geometry Chapter 8: Similarity

About This Chapter

The Similarity chapter of this Big Ideas Math Geometry Companion Course aligns with the same chapter in the Big Ideas Math Geometry textbook. These simple and fun video lessons are about five minutes long and help you learn the essential lessons about similar polygons and triangles.

How It Works:

  • Find the lesson within this chapter that corresponds to what you're studying in the Similarity chapter of your textbook.
  • Watch fun videos that cover the similarity concepts you need to learn or review.
  • Complete the quiz after watching each video lesson to test your understanding.
  • If you need additional help, rewatch the videos until you've mastered the material, or submit a question for one of our instructors.

Chapter Topics

You'll learn all of the geometry topics covered in the textbook chapter, including:

  • How to define similar polygons
  • Determining the area of similar polygons
  • Identifying similar triangles
  • The angle bisector theorem

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6 Lessons in Chapter 8: Big Ideas Math Geometry Chapter 8: Similarity
Test your knowledge with a 30-question chapter practice test
Similar Polygons: Definition and Examples

1. Similar Polygons: Definition and Examples

Watch this video to learn what makes two polygons similar to each other. You'll also learn the one distinguishing aspect of similar polygons and see an example of how to compare two polygons.

Finding Perimeter & Area of Similar Polygons

2. Finding Perimeter & Area of Similar Polygons

Learn how to find the perimeter and area of similar polygons by using the scale factor between the two similar polygons. Work examples for both perimeter and area.

How to Identify Similar Triangles

3. How to Identify Similar Triangles

Similar triangles have the same characteristics as similar figures but can be identified much more easily. Learn the shortcuts for identifying similar triangles here and test your ability with a quiz.

Applications of Similar Triangles

4. Applications of Similar Triangles

Similar triangles are used to solve problems in everyday situations. Learn how to solve with similar triangles here, and then test your understanding with a quiz.

Triangle Proportionality Theorem

5. Triangle Proportionality Theorem

Watch this video lesson to learn all about the triangle proportionality theorem and how you can use this interesting theorem to help you solve problems. Learn how a parallel line can create sides that are proportional to each other.

Angle Bisector Theorem: Definition and Example

6. Angle Bisector Theorem: Definition and Example

Watch this video lesson and learn how you can use the angle bisector theorem to help you find the lengths of missing sides. Also learn how you can identify an angle bisector just by looking at the lengths of the sides of a triangle.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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