Curated OER
30-60-90 Right Triangles in Cabri Jr.
Young mathematicians draw and label right triangles using Cabri Jr. technology. They create other special right triangles and identify the length of the hypotenuse and each leg. Students explore the ratios to determine how the hypotenuse...
West Contra Costa Unified School District
Investigating Special Right Triangles
Scholars first investigate relationships in the side lengths of 30°-60°-90° triangles and 45°-45°-90° triangles. This knowledge then helps them solve problems later in the lesson plan about special right triangles.
Virginia Department of Education
Special Right Triangles and Right Triangle Trigonometry
Right triangles are so special! Use special right triangles to discover the trigonometric ratios. Pairs construct special right triangles and find the values of the ratios of the sides. In the process, they discover the ratios stay the...
Curated OER
Special Right Triangles
Using the Pythagorean Theorem to solve for missing angles, learners evaluate right triangles and their properties.
West Contra Costa Unified School District
Dilations Using Right Triangles
Don't argue with a triangle that has a 90-degree angle. It's always right. Scholars first use right triangles to help draw dilations of points. They continue the instructional activity by applying this skill to draw dilations of polygons.
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,...
EngageNY
Prove the Pythagorean Theorem Using Similarity
Amaze your classes with the ability to find side lengths of triangles immediately — they'll all want to know your trick! Learners use the Pythagorean Theorem and special right triangle relationships to find missing side lengths.
Curated OER
Applying Special Right Triangles
In this geometry worksheet, 10th graders use the theorems regarding right triangles to find the missing length in a special right triangle. The one page worksheet contains eleven questions. Answers are included.
Curated OER
A Special Relationship
Students discover the relationships of the lengths of the sides of right triangles and right triangles using a series of drawings on dot paper. They investigate and solve problems of standard (customary and metric units) and non-standard...
Curated OER
Special Right Triangles
Students identify the different parts of a right triangle. In this geometry lesson, students use the Pythagorean Theorem to identify missing sides and angles of a right triangle. They work with irrational and rational roots.
Curated OER
Designing a Fort
Students explore the concept of right triangles. In this right triangle lesson, students construct a scale model of a tourist attraction similar to Fort Jefferson. Students research aerial photos of Fort Jefferson, then build their...
Curated OER
Pythagorean Theorem and Special Right Triangles
Students review the Pythagorean Theorem and apply it to word problems involving special right triangles.
Curated OER
Right Triangles and The Unit Circle
Young scholars solve right triangles using trigonometry. In this geometry instructional activity, students use the unit circle to identify different trig values. They identify the six trigonometric identities.
Curated OER
Geometric Properties
Students 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.
EngageNY
Sine and Cosine of Complementary Angles and Special Angles
Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the ratios...
Curated OER
Special Right Triangles
Students identify different types of special right triangles. In this geometry lesson, students differentiate between right triangles and isosceles triangles. they construct the triangles using geometry software and make conjectures...
EngageNY
From Circle-ometry to Trigonometry
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
Curated OER
The Right Stuff
Studentsare introduced to the Pythagorean Theorem by exploring right triangles and the squares built on each side. They apply the Pythagorean Theorem to real-world problems. Students u se informal and nonformal arguments of proof (i.e.,...
Alabama Learning Exchange
Unit Circle: Special Angles—Just Know One
It's all about the patterns! Young scholars learn that the unit circle repeats itself in all four quadrants. Using these patterns, they evaluate the sine, cosine, and tangent of special angles.
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
Connecting Area Formulas Produces a Beautiful Formula
In this math worksheet, students find the area of the triangle using the formula of 1/2 bh. Then they find the area using an alternative method.
Curated OER
As the Bird Flies
Students investigate the properties of lines and congruent triangle theorems as well as apply geometric properties and relationships to real-world mathematical problems. Given two different scenarios, they examine maps that have been...
Curated OER
Investigation - Adrienne's Pattern Block Angles
Fifth graders investigate possible solutions to a word problem. They explore properties of polygons and right angles. Students demonstrate proper angle measurement. Students discover patterns.
Curated OER
Investigating the Idea of Sin
Fifth graders use sin to solve problems involving right-angled triangles, Solve equations of the form sin(++) = a, for a between -180++ and 360++. They State and graph the value of sin(++) in special cases. They describe some of the ways...