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.
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.
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 plan, students differentiate between right triangles and isosceles triangles. they construct the triangles using geometry software and make conjectures...
Curated OER
Triangle Tango: Special Right Triangles
Young scholars investigate properties of special right triangles. In this geometry lesson, students use the Pythagorean Theorem to solve for missing angles and sides. They perform reflections.
EngageNY
The Definition of Sine, Cosine, and Tangent
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 triangles.
Curated OER
Solve Right Triangle
In this trigonometric applications worksheet, students solve for the missing side of a right triangle using a trigonometric ratio. There are 46 questions, 10 of which are word problems.
Curated OER
Acute Triangles
Learners study acute triangles. They measure angles using a protractor, then classify the triangles as either right, obtuse, or acute. Everyone creates a design for a Navajo rug using only acute triangles.
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
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 instructional activity, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
Curated OER
Special Right Triangles
In this right triangles worksheet, 10th graders solve and complete 16 various types of problems. First, they find the missing side lengths in each illustration shown. Then, students place the letter of each problem on the lines at the...
Curated OER
Inscribed Right Triangles
Students calculate the measurements of the inscribed angles of a triangle. In this geometry lesson, students relate the hypotenuse of a right triangle and the diameter of a circle to each other. They calculate the diameter of a circle as...
Curated OER
Special Right Triangles Multiple Choice
In this length worksheet, students answer five multiple choice questions concerning lengths using rules of various figures including, triangles, rhombus, diamonds, and circles.
EngageNY
Special Lines in Triangles (part 2)
Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...
Virginia Department of Education
The Pythagorean Relationship
Add up areas of squares to discover the pythagorean relationship. Small groups create right triangles with squares along each side. They calculate the areas of each square and notice the relationship. Groups construct other types of...
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...
Concord Consortium
Triangles: Angle Space
Three angles in a triangle, three-dimensional space, it all seems connected somehow. Given several different triangles, pupils use the three angles of the triangle as coordinates to plot points in three-dimensional space. They explore...
Curated OER
Pythagorean Theorem
Students discover the Pythagorean Theorem. In this discovering the Pythagorean Theorem lesson, students measure the lengths of various triangles to the nearest centimeter. Students record their measurements in a table. Students square...
Mathematics Assessment Project
Pythagorean Triples
What special relationships exist in right triangles? In the high school performance task, learners investigate Pythagorean triples. They then determine rules for the perimeter and area of right triangles given the shortest side.
Curated OER
Special Triangles and Quadrilaterals
In this special triangles learning exercise, students examine given special triangles. They determine the length of a missing side and/or the measurement of a missing angle for given triangles and quadrilaterals. Students justify their...
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Curated OER
Triangle Sum Theorem
Teach your class how to solve problems using the triangle sum theorem. In this geometry lesson, students identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides around to create...
Curated OER
Flying with Pythagoras
A lengthy narrative about Pythagoras and his young scholars precedes an activity in which your young mathematicians practice using the Pythagorean theorem to solve three problems about flight and distance. Answers are provided.