CK-12 Foundation
Angles of Elevation and Depression: Fly-By Calibration
Determine the distance between two trees from afar. Pupils use an interactive resource to create two right triangles using trees and a plane. They determine the horizontal legs of each triangle to find the distance between the two trees.
EngageNY
Using Trigonometry to Find Side Lengths of an Acute Triangle
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
EngageNY
Unknown Angles
How do you solve an equation like trigonometry? Learners apply their understanding of trigonometric ratios to find unknown angles in right triangles. They learn the meaning of arcsine, arccosine, and arctangent. Problems include...
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Curated OER
Finding Trigonometric Ratios
In this finding trigonometric ratios instructional activity, 11th graders solve and complete 22 various types of problems. First, they find the value of each trigonometric ratio to the nearest ten-thousandth. Then, students use a...
Curated OER
Sixteen Angle Pre-calculus Trig Problems
For this angle worksheet, students solve ten multiple choice and six free response questions. These precalculus questions cover angles, radians, and right triangles.
West Contra Costa Unified School District
Introduction to Trigonometric Functions
Scholars first learn the definitions of the sine ratio, the cosine ratio, and the tangent ratio. After mastering these definitions, they use the new information to solve triangles.
Curated OER
A Different Proof of the Law of Cosines
In this proofs worksheet, students construct 1 proof of the law of cosines. Students construct a right triangle within a circle to prove the law of cosines.
Curated OER
Right Triangles and Unit Circles
Students evaluate the six trigonometric values of a trig function. In this trigonometry lesson plan, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and...
Curated OER
Trigonometry Triangles
In this trig worksheet, 11th graders investigate the 6 trigonometry identities and their cofunctions. They use them to solve trig problems as related to right triangles. There are 5 questions with an answer key.
Curated OER
Trigonometry
In this right triangles worksheet, students use trigonometric ratios to determine the length of a side of a triangle or a missing angle measurement. This two-page worksheet contains 20 problems.
Curated OER
Trigonometry Homework
In this right angles worksheet, students use trigonometric ratios to determine the length of a missing side or a missing angle of a right triangle. This two-page worksheet contains 19 problems.
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Curated OER
Geometry Exploration Basic Trig Functions
Tenth graders solve for missing sides on a triangle using the Pythagorean Theorem. In this geometry lesson, 10th graders are introduced to basic trigonometry functions as they solve problems of right triangles. They discuss the...
Curated OER
Easy Worksheet: Trigonometry
For this trigonometry worksheet, students solve 4 short answer problems. Students find the sine, cosecant, secant or cotangent of an angle given a diagram of a right triangle with various measurements labeled.
Curated OER
Trigonometric Ratios
In this trigonometric ratios learning exercise, 10th graders solve 9 different problems that include determining the trigonometric ratios of each triangle. First, they determine the sides and angles of a right triangle that is shown in...
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts...
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
Mathematics Vision Project
Module 7: Modeling with Geometry
Model good modeling practices. Young mathematicians first learn about cross sections and solids of revolution. They then turn their attention to special right triangles and to the Laws of Sine and Cosine.
Curated OER
Tangents
In this tangents activity, students determine the length of a missing side of a right triangles. They use tangent lines to solve problems. This two-page activity contains 11 multi-step problems.
Curated OER
Altitude to the Hypotenuse
Can your class solve right triangles and identify the properties common to right triangles? They will investigate and state the relationship between the altitude to the hypotenuse and the two segments of the hypotenuse formed by the...
Mathed Up!
Trigonometry
Learn how to solve a triangle. Young mathematicians view a video that explains how to apply trigonometry to find missing sides and angles of a right triangle. A worksheet tests their understanding of the concept.
Curated OER
Trigonometry Formula Worksheet
In this trigonometry instructional activity, students solve right triangle problems. They find the sine, cosine and tangent of given triangles. This on-line, interactive instructional activity contains 6 problems. ...