How do you know if a pair of triangles are congruent? Use the lesson to help class members become comfortable identifying the congruence criteria. They begin with an exploration of ASA and SSS criteria through transformations and...

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

Looking for a different approach to triangle congruence criteria? Employ transformations to determine congruent triangles. Learners list the transformations required to map one triangle to the next. They learn to identify congruence...

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

Students will determine if triangles are congruent and state the appropriate congruence theorem. In this geometry lesson, students will determine what information is needed to determine if a pair of triangles are congruent using ASA,...

Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...

In this triangle congruence worksheet, students review 4 triangle congruence properties and 4 examples. Students are then prompted to complete 15 problems analyzing whether two triangles are congruent and determine by which property.

Your geometry learners explore Angle-Side-Angle congruence in this collaborative task. The sum of the interior angles of all triangles being one hundred eighty degrees, is the key learners will discover as they explain their reasoning...

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

In this geometry worksheet, students identify and label triangles as being congruent or not. They use the SSS, ASA or SAS as their description. There are 18 questions with an answer key.

In this congruent triangles worksheet, students solve four multiple choice problems. Students determine which statement is the appropriate reasoning to say that two triangles are congruent.

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...

Students investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, students discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by two rays...

Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by...

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 geometry worksheet, student solve problems with triangles using proofs. They identify the solution based on SSS, SAS, ASA. There are 5 proofs tobe completed.

In this triangle congruence worksheet, 10th graders solve 12 different problems that include determining triangle congruence. First, they prove that triangles are either congruent or similar. Then, students determine whether they can...

In this geometry worksheet, students identify the different ratios of triangles using the theorems. They use SSS, SAS, ASA and AAS to differentiate between triangles. There are 7 questions with an answer key.

Students identify properties of triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.

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...

Your learners will make good use of the Socratic method in a collaborative task that begins with an assumed solution and ends with deeper understanding of the idea of determining two triangles congruent.

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...

Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...

Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...