Curated OER
Eleven Angle Addition Postulate and Adjacent Angle Problems
In this angles worksheet, students use the angle addition postulate, the idea of adjacent angles and the diagrams shown to answer eleven questions
Curated OER
Gougu Rule or Pythagoras' Theorem
Fifth graders explore Pythagoras' Theorem. They examine the pattern linking the length of the hypotenuse of a right angled triangle and the length of the other two sides. Students find an unknown side in right angled triangles.
Curated OER
Discover the Pythagorean Theorem
Middle schoolers explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Middle schoolers complete measurements of the sides of the triangle.
Curated OER
Practice Problems
In this geometry instructional activity, students practice finding the measure of 4 different angles. Students work independently as they refine their ability to correctly calculate the measure of an angle.
Shodor Education Foundation
Squaring the Triangle
Teach budding mathematicians how to square a triangle with an interactive that shows a graphical proof of the Pythagorean Theorem. Pupils alter the lengths of the legs using sliders. Using the inputted lengths, the applet displays the...
Curated OER
Right Triangle Geometry
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.
Curated OER
Skills and Application
In this geometry activity, students identify the different properties of parallel lines cut by a transversal. They identify the different angles created by such lines. There are 16 questions.
Curated OER
Exterior and Interior Angles of Triangles
Tenth graders explore the exterior and interior angles of triangles. They use a theorem in order to prove a theorem about all polygons. Students use the theorem and its applications to find the angles of different types of triangles.
Curated OER
Lines, Rays, and Angles
Third graders read "Pigs on the Ball" by Amy Axelrod and discuss the geometry concepts presented in the book. They use Twizzler sticks and pipe cleaners to represent lines, rays and angles.
Curated OER
Pythagorean Theorem and Special Right Triangles
Students review the Pythagorean Theorem and apply it to word problems involving special right triangles.
Illustrative Mathematics
Tangent to a Circle From a Point
Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about...
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...
Flipped Math
Inverse Trig Ratios
Put trigonometric ratios into inverse. Scholars learn how to find an unknown angle in a right triangle by using inverse trigonometric ratios. The pupils understand how the inverses undo a trigonometric ratio to provide the angle measure....
Flipped Math
Trig Ratios
Take ratios of sides to a new level. Pupils learn the definitions of the three basic trigonometric ratios in right triangles. Using the definitions, scholars find missing lengths in right triangles, based on a known angle. Individuals...
Curated OER
Parallel and Perpendicular Lines
Learners study parallel and perpendicular lines. In this parallel and perpendicular instructional activity, pupils explore 2-D shapes and determine if the sides are parallel or perpendicular.
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...
Shodor Education Foundation
Triangle Area
While the lesson plan 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...
Texas Instruments
What's the Trig?
Learners determine the trigonometric relationships within a triangle as they construct a right triangle on the Ti-89. They find the sine, cosine, and tangent of various angles of their triangle construction.
Illustrative Mathematics
Paper Clip
With minimal setup and maximum freedom, young geometers are encouraged to think outside the box on a seemingly simple application problem. Though the task seems simple, measuring a given paper clip and finding how many 10 meters can...
Curated OER
Applied Trigonometry Problems
In this applied trigonometry problems worksheet, students solve 12 short answer word problems. Students use trigonometric ratios to find angles of elevation and depression. Students find distances between objects using trigonometric...
Curated OER
Right Triangles and Unit Circles
Students evaluate the six trigonometric values of a trig function. In this trigonometry lesson, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and depression.
Mathematics Assessment Project
Hopewell Geometry
Right triangles from 2,000 years ago? Learners investigate different right triangles found in the earthworks of the Hopewell people, a Native American culture that populated the United States from 200BC to AD 500. Learners apply concepts...
Curated OER
Solving Right Triangles
Students investigate the basic trigonometric functions. In this geometry/trigonometry lesson, students explore strategies to solve right triangles using basic trigonometric functions. The lesson includes an application problem in which...
Curated OER
Challenge: Skills and Applications Lesson 3.4
For this geometry worksheet, learners identify the missing angles formed by parallel lines and a transversal. They differentiate between parallel and perpendicular lines. There are four questions.