Curated OER
The Sine and Cosine Ratios
In this geometry worksheet, 10th graders write the ratio that represents the sine and cosine of the indicated angle.  The one page worksheet contains two multiple choice questions. Answers are included.Â
Curated OER
The Laws of Sines and Cosines Made Simple!
Students explore the concept of law of sines and cosines. In this law of sines and cosines lesson, students construct a triangle tool from card stock and markers. Students use their triangle tool to aid in solving problems involving...
Curated OER
Simply Similar at Sea: Simple Triangles
Tenth graders answer a variety of problems based on similar triangle and learn about the rule of thumb. They will test the rule of thumb by estimating the distance to an object in the classroom.
Curated OER
Unit Circle Triangle
Students find the different ratios of a right triangle. In this geometry instructional activity, students apply the concept of the Pythagorean theorem as they identify the different angles and parts of a Unit Circle. They find the ratios...
Mathematics Vision Project
Module 6: Trigonometric Functions
Create trigonometric functions from circles. The first lesson of the module begins by finding coordinates along a circular path created by a Ferris Wheel. As the lessons progress, pupils graph trigonometric functions and relate them to...
EngageNY
Informal Proof of the Pythagorean Theorem
Prove the Pythagorean Theorem using multiple informal proofs. Scholars first develop an understanding of the origins of the Pythagorean Theorem through proofs. They round out the lesson by using the theorem to find missing side lengths...
Curated OER
Triangle Exercises
In this math worksheet, students determine the name for each triangle according to its classification. Then they create a truss construction model.
Curated OER
Triangle Inequality Theorem
Learners 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
The Pythagorean Theorem
In this geometry instructional activity, students solve missing parts of a triangle using the Pythagorean Theorem. There are 19 questions with an answer key.
Curated OER
This Building is Tall
Learners calculate the perimeter of shapes. In this geometry lesson, students relate properties of polygons to the real world. They find length, midpoint and slope.
Curated OER
Understanding Fundamental Trigonometric Identities
Students are introduced to the basic trigonometric identities. Using a diagram, they discover why the parts of the unit circle as named as they are and use equations to finalize the Pythagorean trigonometric identities. They also review...
Curated OER
The Corner Problem
Students explore the concept of the corner problem. In this corner problem lesson, students use the TI-NSpire to determine the maximum length a rod can be and still pass horizontally around a corner. Students use similar triangles to...