Curated OER
Trigonometric Functions of Acute Right Triangles
Learners derive the six trigonometric functions. In this trigonometry lesson, students show their understanding of trigonometric functions as they relate the right triangles. They find the missing angles and side use trig ratios of sine,...
Curated OER
Ratios in Right Triangles
Learners calculate the sides of right triangles in this trigonometric ratios lesson. They use Cabri Jr. software and TI-83 or TI-84 calculators to find the side lengths and their ratios to each other for various triangles. The provided...
Curated OER
Finding the Area of an Equilateral Triangle
The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...
Curated OER
Right Triangles and The Unit Circle
Learners solve right triangles using trigonometry. In this geometry lesson plan, students use the unit circle to identify different trig values. They identify the six trigonometric identities.
Curated OER
Right Triangles and The Pythagorean Theorem
Learners play a game to reinforce concepts of the Pythagorean Theorem. In this geometry lesson, students find the missing angle and lengths of a right triangle. They use properties of trigonometry about sine, cosine and tangent to solve...
Mathematics Assessment Project
Hopewell Geometry
Right triangles from 2,000 years ago? Learners investigate different right triangles found in the earthworks of the Hopewell people, a Native American culture that populated the United States from 200BC to AD 500. Learners apply concepts...
Radford University
Rom/Com Final Scene
You haven't seen this scene before, have you? Young mathematicians first review the Pythagorean Theorem and trigonometry by completing a worksheet. They then consider several problems involving two people running toward each other in a...
Curated OER
Right Triangles and Unit Circles
Students evaluate the six trigonometric values of a trig function. In this trigonometry instructional activity, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and...
Curated OER
Introduction to Trigonometry
Students identify the six trigonometric ratios and properties. In this trig lesson, students define basic trig functions as it relates to solving right triangles. They identify the equation for sine as o/h and cosine as a/h and tangent...
Curated OER
Applications of Triangles
Students apply the properties of a right triangle. In this triangle instructional activity, students describe and compare radians to degrees. They solve problems using the properties and ratios of a right triangle.
Curated OER
Triangles & Congruence, Proportions & Similarity, Right Triangle & Trigonometry
Young scholars are introduced to the topic of congruence and proportions in Geometry. Using technology, they construct and validate the properties of various geometric figures and identify whether it is congruent or proportion to the...
Curated OER
Triangle Inequality Theorem
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
Curated OER
Why We Study Trigonometry
Students investigate the different properties of trigonometry. In this precalculus activity, students find the six different identities of trigonometric ratios. They relate the ratios to that of a right triangle and apply it to real life...
Curated OER
Trigonometry Ratios
Learners identify the different angles and sides of a triangle. In this geometry lesson, students identify the six trigonometric ratios. They graph the graph of each trig function and analyze it.
Curated OER
The Tangent Ratio
Learners calculate the tangent ratio given a right triangle. In this trigonometry lesson, students use a right triangle and the Pythagorean Theorem to solve problems.
Curated OER
Trig Review
Twelfth graders review the 6 identities of trigonometry. In this trig lesson, 12th graders review the importance of the right triangle as it relates to sine, cosine and tangent. They review the basic trig identities and how it relates to...
Curated OER
Trig is SOH Easy!
Students derive the six trigonometric identities. In this trigonometry lesson, students review the parts of a right triangle and use the Pythagorean theorem as a guide to find the trig identities. They find sine, cosine and tangent ratios.
Curated OER
Trigonometry Worksheet 9
Learners use addition and subtraction formulas and special reference triangles to solve a variety of trigonometric problems. Sine, cosine, and tangent problems in both radians and degrees are included.
Illustrative Mathematics
Converse of the Pythagorean Theorem
Use the given tasks and detailed teacher's commentary to introduce your 8th graders to the Pythagorean theorem and its converse. Embedded links to information about Egyptian geometry make your presentation interesting. Consider giving...
Curated OER
Unit Circle and Triangle
Students apply the Unit Circle to solve ratios of triangles. In this geometry lesson, students derive the different ratios of a triangle using the Pythagorean Theorem. They find the angles of a unit circle using a right triangle.
Curated OER
Exploring Trigonometric Ratios
Students calculate the different ratios using a right triangle. In this trigonometry lesson, students identify the sine, cosine and tangent of each side. They find the missing angles using the different ratios.
Curated OER
Unit Circle Triangle
Learners find the different ratios of a right triangle. In this geometry lesson, students apply the concept of the Pythagorean theorem as they identify the different angles and parts of a Unit Circle. They find the ratios of sine,...
Curated OER
Geometry: Solving Right Triangles
Students use trigonometry skills to solve right triangle problems. After the teacher presents several examples, they solve problems on worksheets and discuss their solutions with partners. In a final activity, students determine the...
Curated OER
Trig River
Students calcute distances using trigonometry and angle measurements. They estimate the width of the Trig River, measure it and compare their results with their classmates. They collaborate with a group to research and find the results.