Curated OER
Geometry and Measurement
Students view a right triangle displayed by the teacher. Students measure legs and the interior angles of the triangle. They look for a pattern or relationship between the legs and angles. Students use pegboards and string to create more...
EngageNY
Triangle Congruency Proofs (part 2)
Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...
Texas Instruments
Identifying a Triangle by its Sides and Angles
Identify triangles by their angle measures and side lengths by looking at and measuring angle measures and side lengths. Use Cabri Jr. to construct various triangles, then manipulate the construction to create the 6 types of triangles,...
Curated OER
Review of Triangles
Students investigate the Pythagorean Theorem. For this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
Mathalicious
Been Caught Stealing
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 that explores right triangles and measurement. Full of discussion questions and fun...
Curated OER
Angles in Triangles
Eighth graders translate word problems using mathematical ideas. In this geometry lesson, 8th graders identify angles of triangles using equations and the triangle sum theorem. They create angles with a protractor and straight edge.
Curated OER
Properties of Angles, Lines, and Triangles
In this properties of angles, lines and triangles worksheet, 10th graders solve and complete 28 different problems that include determining the measurement of various figures shown. First, they use the geometric properties and theorems...
Curated OER
Trigonometry Applications
In this geometry worksheet, 10th graders solve application word problems involving the use or right triangle trigonometry, including angle of elevation or depression. The one page interactive worksheet contains five questions. Hints,...
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...
Curated OER
Triangle Side Lengths and Angles Measures
Students identify missing sides and angles. In this geometry lesson, students use triangular theorems to identify the missing sides. They use the Pythagorean Theorem to find the different ratios of each side.
Curated OER
Polygons and Sketching
For this geometry worksheet, learners define and draw quadrilaterals. They differentiate between the different shapes. There are 3 questions with an answer key.
Curated OER
Pyramids- Slant Height and Altitude
Young scholars calculate the height and altitude of a pyramid. In this geometry lesson, students define the parts that make up a pyramid. They use the Pythagorean Theorem to find the missing parts of a pyramid.
Curated OER
Angle-Side Relationships
Students calculate the different sides and angles of a triangle. In this geometry lesson, students use triangular properties to define the relationship between two triangle. They identify missing angles using the interior angle theorem.
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
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
Area of Polygons
Students engage in a lesson that is about the concept of polygons and focuses upon finding the area. They use formulas provided in the lesson in order to solve problems given by the teacher for independent practice. Geometric figures are...
Curated OER
The Truth About Triangles And Proofs
Students engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the importance of...
Curated OER
Right Triangles
Learners classify triangles and make connections regarding angle measurements and attributes of acute, right, and obtuse triangles. They listen to teacher define and explain triangles. Everyone imagines a place where a broken wing for a...
Curated OER
Polygons All Around Us!
Students explore the concept of polygon properties. In this polygon properties lesson plan, students draw polygons with different numbers of sides such as pentagons, octagons, hexagons, etc. Students identify different geometric shapes...
Geometry Help
Geometry Help: Isosceles Triangles
Explains the basic concept of isosceles triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
Oswego City School District
Regents Exam Prep Center: Isosceles Triangle Theorem
Material to supplement instruction on isosceles triangles: a lesson with related theorems and examples; an online practice quiz for students to take and check their answers; and guidelines for proving the isosceles triangle theorem.
CK-12 Foundation
Ck 12: Geometry: Triangle Relationships Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide reviews terminology for triangles, triangle properties, different types of triangles, and interior and exterior angle theorems.
CK-12 Foundation
Ck 12: Interactive Geometry: 4.4 Theorems About Triangles
Discover some theorems about triangles.
CK-12 Foundation
Ck 12: Geometry: Bisectors, Medians, Altitudes Study Guide
This study guide on bisectors, medians, and altitudes covers key vocabulary, different theorems, and facts about the altitude and triangles. It is available for download with free registration.