Ch 10: Holt Geometry Chapter 10: Trigonometry

About This Chapter

The Trigonometry chapter of this Holt Geometry Textbook Companion Course helps students learn the essential geometry lessons of trigonometry. Each of these simple and fun video lessons is about five minutes long and is sequenced to align with the Trigonometry textbook chapter.

How it works:

  • Identify the lessons in Holt Geometry's Trigonometry chapter with which you need help.
  • Find the corresponding video lessons within this companion course chapter.
  • Watch fun videos that cover the 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:

  • Finding tangent ratios
  • Solving problems with sines and cosines
  • Extending ratios used in trigonometry
  • Using the laws of sines and cosines
  • Properties of vectors
  • Plotting rotations

Holt Geometry is a registered trademark of Holt, Rinehart and Winston, which is not affiliated with

6 Lessons in Chapter 10: Holt Geometry Chapter 10: Trigonometry
Test your knowledge with a 30-question chapter practice test
Practice Finding the Trigonometric Ratios

1. 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.

Trigonometry: Sine and Cosine

2. Trigonometry: Sine and Cosine

Learn an easy trick to help you solve trigonometry problems, including problems with sine, cosine and inverse trig functions. At the end of this lesson, you'll know what SohCahToa means and how to use it.

List of the Basic Trig Identities

3. List of the Basic Trig Identities

There are specific trig functions that have very special and very simple relationships with each other. Learn the main one and how you can use it to understand the others.

Trigonometric Ratios and Similarity

4. 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.

Law of Sines: Definition and Application

5. Law of Sines: Definition and Application

Don't get stuck trying to find missing sides or angles in a triangle. Use the Law of Sines to rescue you from any perilous triangle in which you have just a few pieces of information.

Law of Cosines: Definition and Application

6. Law of Cosines: Definition and Application

In this lesson, we'll learn how to solve problems involving three sides and one angle in a triangle. The Law of Cosines, a modification of the Pythagorean Theorem, will save the day.

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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