Ch 9: Geometry & Properties of Triangles

About This Chapter

Get a comprehensive overview of geometry and properties of triangles by reviewing the bite-sized lessons in this self-paced math chapter. Test your knowledge of this subject and ensure you're able to succeed on an assignment, project or test by taking this chapter's practice quizzes and exam.

Geometry & Properties of Triangles - Chapter Summary

This chapter offers a fun and engaging examination of geometry and properties of triangles. Entertaining lessons make it easily to understand angles, sides, the Pythagorean theorem, the triangle proportionality theorem and much more. Enjoy the ability to access these lessons anytime using any computer or mobile device with an Internet connection. When ready, check your understanding of these lessons by taking multiple-choice quizzes and a chapter exam. Track your progress through this chapter and submit lesson topic questions to our experts via the Dashboard. Once you've completed this chapter, you will be able to:

  • Classify triangles by sides and angles
  • Complete angle and triangle practice problems
  • Define the Pythagorean theorem
  • Practice the application of the Pythagorean theorem
  • Share the meaning of the triangle proportionality theorem
  • Prove angle relationships
  • Read and interpret circle graphs and central angles

7 Lessons in Chapter 9: Geometry & Properties of Triangles
Test your knowledge with a 30-question chapter practice test
Classifying Triangles by Angles and Sides

1. Classifying Triangles by Angles and Sides

Not all triangles are the same. There are equilateral, isosceles and scalene triangles. Then there are right, acute and obtuse triangles. In this lesson, we'll learn how to classify triangles using their sides and angles.

Angles and Triangles: Practice Problems

2. Angles and Triangles: Practice Problems

Want more practice solving with angle pairs? How about more review for solving angles in triangles? Look no further. Get more practice here, and test your ability with a quiz.

Pythagorean Theorem: Definition & Example

3. Pythagorean Theorem: Definition & Example

Learn what the Pythagorean Theorem says about a right triangle and the relationships of its three sides to each other by watching this video lesson. Also learn how you can use this to your advantage when solving problems.

The Pythagorean Theorem: Practice and Application

4. The Pythagorean Theorem: Practice and Application

The Pythagorean theorem is one of the most famous geometric theorems. Written by the Greek mathematician Pythagoras, this theorem makes it possible to find a missing side length of a right triangle. Learn more about the famous theorem here and 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.

Proving Angle Relationships

6. Proving Angle Relationships

In this lesson, you'll learn to prove angle relationships using properties of congruent, complementary, and supplementary angles. Learn the concepts and apply them on practice problems.

Reading & Interpreting Circle Graphs & Central Angles

7. Reading & Interpreting Circle Graphs & Central Angles

Circle graphs are some of the most useful graphical descriptions of data around. However, without knowing how to find central angles, their usefulness is limited, and their creation is difficult. In this lesson, we learn how to find central angles while using and creating circle graphs.

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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