Ch 22: Triangle Trigonometry: Help and Review

About This Chapter

The Triangle Trigonometry chapter of this High School Trigonometry Help and Review course is the simplest way to master trigonometry concerning triangles. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of triangle trigonometry.

Who's it for?

Anyone who needs help learning or mastering high school trigonometry material will benefit from taking this course. There is no faster or easier way to learn high school trigonometry. Among those who would benefit are:

  • Students who have fallen behind in understanding how the Pythagorean theorem can be used to find missing angles and sides of right triangles
  • Students who struggle with learning disabilities or learning differences, including autism and ADHD
  • Students who prefer multiple ways of learning math (visual or auditory)
  • Students who have missed class time and need to catch up
  • Students who need an efficient way to learn about triangle trigonometry
  • Students who struggle to understand their teachers
  • Students who attend schools without extra math learning resources

How it works:

  • Find videos in our course that cover what you need to learn or review.
  • Press play and watch the video lesson.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Verify you're ready by completing the Triangle Trigonometry chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the Triangle Trigonometry chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any triangle trigonometry question. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

This chapter helps students review the concepts in a triangle trigonometry unit of a standard high school trigonometry course. Topics covered include:

  • Trigonometric ratios and similarity
  • Sines and cosines of complementary angles
  • Applications of the Pythagorean theorem
  • Triangle area
  • The law of sines
  • The law of cosines

13 Lessons in Chapter 22: Triangle Trigonometry: Help and Review
Test your knowledge with a 30-question chapter practice test
Trigonometric Ratios and Similarity

1. 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

2. 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.

The Pythagorean Theorem: Practice and Application

3. 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.

Finding Distance with the Pythagorean Theorem

4. Finding Distance with the Pythagorean Theorem

How much faster is it to cut the corners in a race around the block? In this lesson, review the Pythagorean Theorem, and figure out how to solve without a right triangle.

Trigonometry and the Pythagorean Theorem

5. Trigonometry and the Pythagorean Theorem

Explore how the Pythagorean Theorem can be used in conjunction with trigonometric functions. In this lesson, take an inverse trigonometric function, and define all three sides of a right triangle.

Perfect Square Binomial: Definition & Explanation

6. Perfect Square Binomial: Definition & Explanation

Learn what sets perfect square binomials apart from other trinomials in the math world. You will also learn an easy method to identify them along with a simple procedure to factor them.

Pythagorean Triple: Formula & Examples

7. Pythagorean Triple: Formula & Examples

In this lesson you will learn about primitive and non-primitive Pythagorean triples - sets of positive integers that satisfy the Pythagorean theorem. See if you can identify Pythagorean triples.

Special Triangle: Rules & Formulas

8. Special Triangle: Rules & Formulas

Finding the missing side of a triangle is pretty simple when that triangle is 'special'. In this lesson, you will learn about two types of special right triangles, their properties and shortcuts to find the missing side length.

Tangent in Trigonometry: Definition & Overview

9. Tangent in Trigonometry: Definition & Overview

One of the basics of trigonometry, the tangent is quite a helpful tool. In this lesson, learn how you can use the tangent to find missing sides of triangles and how to find important angles for real world applications.

Tangent Ratio: Definition & Formula

10. Tangent Ratio: Definition & Formula

The tangent ratio is a tool used with right triangles that allows one to find the length of the sides of a triangle given the degree of its angles. It can also be used to find the degrees of its angle given the length of two of its sides.

Tangents: Definition & Properties

11. Tangents: Definition & Properties

In this lesson, we will cover the tangent as it is used in calculus. You will learn the process of finding the tangents of curves and will also find out what defines tangents in calculus.

Triangular Pyramid: Definition, Formula & Examples

12. Triangular Pyramid: Definition, Formula & Examples

Learn what a triangular pyramid is and how to find its volume and surface area. We will use examples and definitions to familiarize ourselves with these types of pyramids.

Calculating Angles for a 5-12-13 Triangle

13. Calculating Angles for a 5-12-13 Triangle

How do you calculate the angles of a triangle when you only know the lengths of the sides? This lesson will go over a step-by-step process to calculate the angles, using a triangle whose sides are 5, 12 and 13 units long.

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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Other Chapters

Other chapters within the High School Trigonometry: Help and Review course