Interactive
Mangahigh

Mangahigh: Shape: 3 D Trigonometry

For Students 9th - 10th Standards
Test your knowledge of determing the lengths and angles of right triangles.
Unit Plan
CK-12 Foundation

Ck 12: Trigonometry: Pythagorean Theorem to Classify Triangles

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] Use the Pythagorean Theorem to determine if triangles are acute, obtuse, or right triangles.
eBook
Mathigon

Mathigon: Geometry: Triangles and Trigonometry: Properties of Triangles

For Students 9th - 10th Standards
This lesson focuses on the properties of triangles, a closed shape that has three sides, three vertices, and and three internal angles. There are different types of triangles such as a right triangle, obtuse, and acute based on the...
Activity
TeachEngineering

Teach Engineering: Trigonometry via Mobile Device

For Teachers 9th - 10th
Students investigate the relationships between angles and side lengths in right triangles with the help of materials found in the classroom and a mobile device.
Lesson Plan
TeachEngineering

Teach Engineering: Handheld Trigonometry

For Teachers 9th - 10th Standards
In addition to understanding the concept of similar right triangles and how they apply to trigonometric ratios, students explore a clinometer app, and discover how it can be used to test the mathematics underpinning trigonometry.
Activity
Math2

Math2.org: Trigonometry Functions

For Students 9th - 10th Standards
A complete look at trig functions. From an "overview," page giving general definitions and important vocab words, to a listing of the 12 trig functions, to an explanation of the three modes used in trigonometry, to the procedures of how...
Whiteboard
ClassFlow

Class Flow: Trigonometry

For Teachers 9th - 10th Standards
[Free Registration/Login Required] Students explore trigonometric functions using the interactive features of Activstudio. Students apply their understanding of trigonometric sense to determine the side lengths and angles of various...
Activity
Texas Instruments

Texas Instruments: What's the Trig?

For Teachers 9th - 10th Standards
Students will be introduced to right triangle trigonometry. They will use the TI-89 and Geometer's Sketchpad to construct a right triangle and calculate sin, cosine, and tangent of various acute angles.
Unknown Type
Khan Academy

Khan Academy: Solve for an Angle in Right Triangles

For Students 9th - 10th Standards
Given two sides in a right triangle, find one of the acute angles using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Unit Plan
CK-12 Foundation

Ck 12: Trigonometry: Pythagorean Theorem for Solving Right Triangles

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] Finding unknown sides in a triangle using other sides and angles.
Unknown Type
Khan Academy

Khan Academy: Solve for an Angle in Right Triangles

For Students 9th - 10th Standards
Given two sides in a right triangle, find one of the acute angles using trigonometry.
Unit Plan
CK-12 Foundation

Ck 12: Right Triangles, Bearings, and Other Applications

For Students 10th - 12th
[Free Registration/Login may be required to access all resource tools.] Find distances using angles expressed as bearings. Here you'll learn how to relate right triangle relationships to course bearings.
Activity
Exploratorium

Exploratorium: Ilion High: Build a Clinometer

For Students 9th - 10th Standards
Instructions for building a clinometer are given on this page. Clinometers can be used to measure the angle of elevation of a right triangle, and in turn find the height of large objects.
eBook
Math Planet

Math Planet: Pre Algebra: Trigonometry

For Students 9th - 10th
Learn about trigonometry by viewing examples and a video lesson.
Unit Plan
CK-12 Foundation

Ck 12: Trigonometry: Pythagorean Theorem for Solving Right Triangles

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] This lesson applies the trigonometric ratios and their inverses to real-life situations.
Handout
Purple Math

Purplemath: Special Angle Values: 30 60 90 and 45 45 90 Triangles

For Students 9th - 10th
Explains a simple pictorial way to remember basic reference angle values. Provides other memory aids for the values of trigonometric ratios for these "special" angle values, based on 30-60-90 triangles and 45-45-90 triangles.
Unknown Type
Khan Academy

Khan Academy: Solve for a Side in Right Triangles

For Students 9th - 10th Standards
Given one side length and an acute angle in a right triangle, find another side using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Unknown Type
Khan Academy

Khan Academy: Solve for a Side in Right Triangles

For Students 9th - 10th Standards
Given one side length and an acute angle in a right triangle, find another side using trigonometry.
Activity
TeachEngineering

Teach Engineering: You've Got Triangles!

For Teachers 6th - 8th
Students learn about trigonometry, geometry and measurements while participating in a hands-on interaction with LEGO MINDSTORMS NXT technology. First they review fundamental geometrical and trigonometric concepts. Then, they estimate the...
Handout
Math Open Reference

Math Open Reference: Introduction to Trigonometry

For Students 9th - 10th
An introductory reference guide to trigonometry. It provides definitions and examples that enhance further explanation. Includes links to related topics.
Lesson Plan
Khan Academy

Khan: Lesson 16: Part 2 Coordinate Geometry; Trigo and Radians; Complex Numbers

For Teachers 9th - 10th Standards
2 OF 2 FOR ADDITIONAL TOPICS IN MATH. Students will use the coordinate plane and equations of lines and circles to describe figures; create the equation of a circle given the figure or use the structure of a given equation to determine a...
Activity
Interactive Mathematics

Interactive Mathematics: Trigonometric Functions

For Students 9th - 10th
Just about everything you need to know about trigonometry can be found here. Interactive examples and demonstrations help to enhance the lessons. Although not required, the tutorial uses Live Math and Scientific Notebook.
Handout
Purple Math

Purplemath: Inverses of Trigonometric Ratios

For Students 9th - 10th Standards
You know that you can take side lengths and find trig ratios, and you know you can find trig ratios (in your calculator) for angles. What is missing is a way to go from the ratios back to the original angles. And that is what "inverse...
Unit Plan
Oswego City School District

Regents Exam Prep Center: Area of a Triangle and Parallelogram Using Trig

For Students 9th - 10th Standards
How can trigonometry be used to find the area of a triangle or parallelogram? Does the triangle need to be a right triangle, and how accurate can the results possibly be? The answers to these questions are found here along with several...