Worksheet
Curated OER

Determine the Measure of an Angle of a Right Triangle.

For Students 10th - 11th
In this geometry worksheet, students solve word problems by finding the values of missing angles and missing sides of triangles. They review their trigonometric properties of a right triangle. There are 9 problems with an answer key.
Lesson Plan
Curated OER

Right Triangle Geometry

For Teachers 9th - 11th
Students study the basic principles of right triangle geometry needed to solve for unknown values of a right triangle. They apply and master the principles of right triangle geometry by solving problems.
Worksheet
Curated OER

Classifying Triangles Using Sides

For Students 4th - 5th
In this geometry worksheet, students answer 8 fill in the blank questions where they must examine 5 different complex geometric figures to classify triangles.
Lesson Plan
Curated OER

Special Right Triangles

For Teachers 7th - 9th
Students identify the different parts of a right triangle. In this geometry instructional activity, students use the Pythagorean Theorem to identify missing sides and angles of a right triangle. They work with irrational and rational roots.
Worksheet
Curated OER

Similar Right Triangles-Introductions to Trigonometry

For Students 9th - 10th
In this geometry worksheet, students examine similar right triangles as the basis for the foundation of trigonometry. Students define the basic trigonometric functions and use a calculator to find the trigonometric value of an angle. The...
Lesson Plan
Curated OER

Right Triangles and The Unit Circle

For Teachers 8th - 10th
Students solve right triangles using trigonometry. In this geometry lesson, students use the unit circle to identify different trig values. They identify the six trigonometric identities.
Worksheet
Curated OER

Right Triangle

For Students 8th - 9th
In this right triangle worksheet, students find the length of sides of a right triangle. This one-page worksheet contains 1 problem.
Worksheet
Curated OER

Right Triangle

For Students 8th - 9th
In this right triangle worksheet, students find the lengths of the sides of a triangle. This one-page worksheet contains 1 problem.
Lesson Plan
Curated OER

Right Triangles and The Pythagorean Theorem

For Teachers 8th - 9th
Pupils 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...
Lesson Plan
EngageNY

The Definition of Sine, Cosine, and Tangent

For Students 9th - 10th Standards
Introduce your classes to a new world of mathematics. Pupils learn to call trigonometric ratios by their given names: sine, cosine, and tangent. They find ratios and use known ratios to discover missing sides of similar...
Worksheet
K12 Reader

Classifying Triangles

For Students 2nd - 3rd Standards
Bring math and reading informational text together with a reading comprehension lesson. After kids read about isosceles, scalene, and equilateral triangles, they answer five comprehension questions to demonstrate how they can use context...
Lesson Plan
Mathematics Assessment Project

Solving Problems with Circles and Triangles

For Teachers 9th - 12th Standards
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.
Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 7th - 10th
In this measurement lesson, learners examine the Pythagorean Theorem, perimeter, and areas of right triangles. They record their measurements and research their findings on a grid.
Lesson Plan
Curated OER

Area Measures and Right Triangles

For Teachers 9th - 12th Standards
Your class will investigate the relationship among different triangles. This geometry lesson, demonstrates how to make a connection between triangles and the Pythagorean Theorem. They identify the missing side or angle of a triangle.
Lesson Plan
EngageNY

Unknown Angles

For Students 9th - 10th Standards
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...
Handout
McGraw Hill

Triangles

For Students 4th - 7th Standards
After reviewing characteristics of seven types of triangles, young geometers discover how to find the missing angle of a triangle. Then, they practice identifying triangles, find missing angles, and find missing side lengths of...
Assessment
Concord Consortium

Isosceles Triangle Spaces

For Students 7th - 10th Standards
How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...
Lesson Plan
Everyday Mathematics

Mathematics Within: Slope and Triangles

For Teachers 8th - 10th Standards
Learners discover a method for determining the slope of a line by creating and comparing similar triangles. They fold coordinate grids to make three similar triangles then measure the sides to compare the relationships between the...
Lesson Plan
Curated OER

Discover the Pythagorean Theorem

For Teachers 6th - 8th
Learners explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Learners complete measurements of the sides of the triangle.
Lesson Plan
Curated OER

Indirect Proof and Inequalities in one Triangle

For Teachers 10th
In this geometry worksheet, 10th graders complete an indirect proof and order the sides or angles of a triangle. Also, students determine if a triangle can have sides with the given lengths. The two page worksheet contains twelve...
Assessment
EngageNY

End-of-Module Assessment Task - Geometry (module 2)

For Students 9th - 10th Standards
Increase the level of assessment rigor with the test of performance tasks. Topics include similar triangles, trigonometric ratios, Law of Sines, Law of Cosines, and trigonometric problem solving. 
Lesson Plan
Curated OER

Geometric Properties

For Teachers 9th - 12th
Young scholars find triangular angles using the angle theorem. In this geometry lesson, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
Lesson Plan
Curated OER

The Pythagorean Theorem and Classifying Triangles

For Teachers 9th - 12th Standards
Through the examination of the relationship between the lengths of the sides of a triangles learners will learn the classification of triangles (acute, right, or obtuse).
Lesson Plan
Curated OER

Constructions Triangles

For Teachers 10th Standards
Learners explore the difference between a construction and a drawing. They focus on various ways to construct different types of triangles. The lesson is an application of Cabri Jr. and reinforces the difference between a constructions...