Ch 9: McDougal Littell Geometry Chapter 9: Right Triangles and Trigonometry

About This Chapter

The Right Triangles and Trigonometry chapter of this McDougal Littell Geometry Textbook companion course helps students learn essential geometry lessons of right triangles and trigonometry. Each of these simple and fun video lessons is about five minutes long and is sequenced to align with the Right Triangles and Trigonometry textbook chapter.

How it works:

  • Identify the lessons in the McDougal Littell Geometry Textbook Right Triangles and Trigonometry chapter with which you need help.
  • Find the corresponding video lessons within this companion course chapter.
  • Watch fun videos that cover the right triangles and trigonometry topics you need to learn or review.
  • Complete the quizzes 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.

Students will learn:

  • Properties of right triangles
  • Proportions in right triangles
  • Using a geometric mean to solve problems
  • The Pythagorean theorem in practice and application
  • The Pythagorean theorem: converse and special cases
  • Classifying triangles by angle measures
  • Types and properties of special right triangles
  • Side lengths of special right triangles
  • Introduction to sines, cosines and tangents
  • Trigonometric ratios and similarity
  • Practice finding the trigonometric ratios
  • Solving right triangles
  • Problems requiring solving right triangles
  • Definition and types of vectors
  • Finding the magnitude of a vector
  • Explanation and examples of vector addition with a geometric approach

McDougal Littell Geometry is a registered trademark of McDougal Littell, which is not affiliated with Study.com.

6 Lessons in Chapter 9: McDougal Littell Geometry Chapter 9: Right Triangles and Trigonometry
Test your knowledge with a 30-question chapter practice test
Properties of Right Triangles: Theorems & Proofs

1. Properties of Right Triangles: Theorems & Proofs

In this lesson, you will learn about the properties of and theorems associated with right triangles, which have a wide range of applications in math and science. Specifically, we will discuss and prove the Pythagorean theorem and the right triangle altitude theorem. Let's get started.

The Pythagorean Theorem: Practice and Application

2. 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.

The Pythagorean Theorem: Converse and Special Cases

3. The Pythagorean Theorem: Converse and Special Cases

The Pythagorean Theorem is a famous theorem for right triangles. Watch this video to learn how the Pythagorean Theorem relates to the law of cosines and how the converse of the Pythagorean Theorem can help you identify right triangles.

Special Right Triangles: Types and Properties

4. Special Right Triangles: Types and Properties

Not all right triangles are the same. In this lesson, we'll look at two special right triangles (30-60-90 and 45-45-90) that have unique properties to help you quickly and easily solve certain triangle problems.

Trigonometric Ratios and Similarity

5. Trigonometric Ratios and Similarity

Where do terms like sine, cosine and tangent come from? In this lesson, we'll learn about how similarity with right triangles leads to trigonometric ratios.

Practice Finding the Trigonometric Ratios

6. Practice Finding the Trigonometric Ratios

So you know what sine, cosine and tangent are. Great! But how do you use them? Find out how in this lesson as we find missing sides and angles using trigonometric ratios.

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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