High schoolers explore the concept of congruent triangles.  In this congruent triangles lesson, students use Cabri Jr. to construct two congruent triangles using circles.  High schoolers determine if the two triangles are...

Learners explore the concept of similarity and congruence. In this similarity and congruence lesson, students cut out strips of paper and form a triangle. Learners try to prove that their triangles are congruent using the SSS theorem of...

Triangles are all about threes, and practicing proving postulates is a great way to get started. The first page of the worksheet provides a brief introduction of the different properties and postulates. The remaining pages contain...

Students explore the concept of similarity and congruence. In this similarity and congruence instructional activity, students identify and verify whether or not two figures are similar, congruent, or neither. Students use postulates and...

Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...

Students differentiate between similarity and congruence using polygons. In this geometry lesson plan, students label triangles based on their properties. They find missing sides and angles using the interior sum theorem.

Young scholars discover three lettered postulates that prove triangles congruent.

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...

I'd like to prove that this worksheet has a lot to offer. Seven problems using triangles and parallelograms practice the traditional method of a two-column proof. After the worksheet is some practice problems that show worked out...

In this congruent triangles worksheet, 10th graders solve 5 various types of geometry problems related to triangles. First, they draw and label triangles, indicating the additional pairs of corresponding parts that would have to be...

In this triangle congruence worksheet, students select the postulate that is being illustrated to prove congruence between triangles. The worksheet is self-scoring. Once students select the "check your work" link, they are given their...

In this triangle theorems activity, students identify the theorem used to prove the specified triangular relationship. Students are shown an illustration of two or more triangles. They identify the postulate that would be used to prove...

In this triangle congruence learning exercise, students use SSS, ASA, AAS and HL to determine the congruence of triangles.  They identify the theorem that proves congruence.  This three-page learning exercise contains 4...

In this proving triangles congruent worksheet, 10th graders solve 5 different problems that include proofs and proving congruence in triangles. First, they determine which postulate can be used to prove the triangles congruent and mark...

Tenth graders explore congruent triangles.  In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles are congruent by SSS, ASA, AAS, or SAS. 

Young scholars investigate triangles and congruences. In this geometry lesson plan, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.

Ninth graders find the height of every day objects using techniques learned through postulates that allow triangles in a problem to be similar. They calculate the length of a missing side and solve proportions.

In this lesson on congruent triangles, students explore how to use postulates to identify if triangles are congruent by SSS, SAS, ASA, and AAS.

[Free Registration/Login may be required to access all resource tools.] Provides an overview of triangle congruence, including key terms, properties of congruent triangles, triangle postulates and theorems, and special triangles.

[Free Registration/Login Required] This lesson helps teach congrence in triangles. Includes practice with postulates, theorems, and logical reasoning.