+
Lesson Plan
Virginia Department of Education

Special Right Triangles and Right Triangle Trigonometry

For Teachers 9th - 11th Standards
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...
+
Lesson Plan
West Contra Costa Unified School District

Investigating Special Right Triangles

For Teachers 9th - 12th
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 about special right triangles.
+
Interactive
CK-12 Foundation

Special Triangle Ratios: Special Right Triangle Ratios

For Students 9th - 12th Standards
Go from one side length to any other side length with special right triangles. Individuals use the interactive to investigate the ratio of sides in 45-45 and 30-60 right triangles. Scholars make generalizations about the types of special...
+
Lesson Plan
Curated OER

Special Right Triangles

For Teachers 10th - 12th
In this special right triangle worksheet, students use the trigonometric functions to determine angle measurement or the length of one side of a right triangle. This one-page worksheet contains 18 problems. Answers are provided at the...
+
Instructional Video20:12
2
2
Flipped Math

Special Right Triangles I

For Students 9th - 12th
Introduce a special relationship with right triangles. Learners discover the ratio of the sides in a 30-60-90 triangle. After watching several examples and seeing two different methods, pupils find unknown sides in triangles. Scholars...
+
Worksheet
Curated OER

Special Right Triangles Homework

For Students 9th - 12th
In this geometry worksheet, students solve both kinds of special right triangles. There are 12 questions with multiple parts.
+
Lesson Plan
Curated OER

Special Right Triangles

For Teachers 9th - 12th Standards
Using the Pythagorean Theorem to solve for missing angles, students evaluate right triangles and their properties.
+
Lesson Plan
EngageNY

Prove the Pythagorean Theorem Using Similarity

For Students 9th - 10th Standards
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.
+
Instructional Video10:02
2
2
Flipped Math

Special Right Triangles II

For Students 9th - 12th
Show students that right triangles are radical. Learners see how the lengths of the sides of a 45-45-90 triangle relate. Using that relationship, pupils observe how to find any of the lengths given one side of a triangle. They go on to...
+
Interactive
CK-12 Foundation

Lengths of Sides in Isosceles Right Triangles: Paper Football

For Students 9th - 12th Standards
Fuse sports and geometry by having your class create paper footballs—that are actually isosceles right triangles! Scholars use an interactive to create an isosceles right triangle to model a paper football. From the information in the...
+
Interactive
CK-12 Foundation

Relationships of Sides in 30-60-90 Right Triangles: Truck on a Mountain Road

For Students 9th - 12th Standards
Determine the change in elevation on a mountain road. Individuals use the interactive to simulate a truck driving up a mountain road with a 30-degree incline. They determine missing sides of a 30-60 right triangle to find horizontal and...
+
Unit Plan
Radford University

Right Triangle Applications: Lessons 1 and 2

For Students 9th - 12th Standards
Use right triangles for more than just mathematical problems. The first two lessons of a unit ask pupils determine distances between cities by using the Pythagorean Theorem and a map. To cement understanding, learners use trigonometric...
+
Unit Plan
Radford University

Right Triangle Sports

For Teachers 9th - 12th Standards
Who knew math could help with sports? An invigorating set of lessons encourages learners to apply right triangles in baseball, volleyball, hockey, football, and soccer. They use the Pythagorean Theorem, Pythagorean triples, special right...
+
Instructional Video7:06
2
2
Flipped Math

Unit 7 Review: Right Triangles

For Students 9th - 12th Standards
It is all right to spend some time with a review. After watching a short review video covering the materials from the unit, pupils work through 23 review problems. Scholars work on problems involving the Pythagorean Theorem and its...
+
Worksheet
Curated OER

Special Right Triangles

For Students 9th - 12th
In this special right triangles worksheet, students solve 15 short answer problems. Students use trigonometric functions to find missing side lengths of various right triangles.
+
Lesson Plan
Curated OER

Applying Special Right Triangles

For Teachers 10th
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.
+
Lesson Plan
EngageNY

Special Triangles and the Unit Circle

For Teachers 11th - 12th Standards
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
+
Lesson Plan
Shodor Education Foundation

Triangle Area

For Teachers 6th - 9th Standards
While the lesson focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can they...
+
Lesson Plan
Mathalicious

Been Caught Stealing

For Teachers 6th - 8th Standards
You're safe, when calculating the odds of stealing second base! Learners compare the rate of a runner to the distance the ball travels, in a lesson plan that explores right triangles and measurement. Full of discussion questions and fun...
+
Lesson Plan
EngageNY

Special Relationships Within Right Triangles—Dividing into Two Similar Sub-Triangles

For Students 9th - 10th Standards
Why are right triangles so special? Pupils begin their study of right triangles by examining similar right triangles. Verifying through proofs, scholars recognize the three similar right triangles formed by drawing the altitude. Once...
+
Lesson Plan
Alabama Learning Exchange

Unit Circle: Special Angles—Just Know One

For Students 9th - 12th Standards
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.
+
Lesson Plan
Curated OER

30-60-90 Right Triangles in Cabri Jr.

For Teachers 9th - 12th Standards
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...
+
Worksheet
Curated OER

Special Right Triangles

For Students 10th
In this special right triangles worksheet, 10th graders solve 7 various problems with various types of right triangles. First, they identify the two special types of right triangles, the 45-45-90 degree triangle and the 30-60-90 right...
+
Lesson Plan
Curated OER

Pythagorean Theorem and Special Right Triangles

For Teachers 9th - 11th
Students review the Pythagorean Theorem and apply it to word problems involving special right triangles.