Illustrative Mathematics
Illustrative Mathematics: G Co Why Does Sas Work?
In this task, students must explain the given reasoning for why triangle ABC is congruent to triangle DEF using the language of reflections. Aligns with G-CO.B.8.
Math Open Reference
Math Open Reference: Congruence
A complete reference guide to congruence including congruent triangles and polygons. It provides definitions, animation, and interactive activities that enhance further explanation.
CK-12 Foundation
Ck 12: Geometry: Congruent Triangles
[Free Registration/Login may be required to access all resource tools.] In this lesson students determine whether two triangles are congruent. Students examine guided notes, review guided practice, watch instructional videos and attempt...
CK-12 Foundation
Ck 12: Geometry: Proofs Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide reviews proofs: algebraic proof, properties of congruence, and geometric proofs (two-column).
CK-12 Foundation
Ck 12: Geometry: Congruence Statements
[Free Registration/Login may be required to access all resource tools.] In this lesson students deduce information about triangles with congruence statements. Students examine guided notes, review guided practice, watch instructional...
CK-12 Foundation
Ck 12: Geometry: Comparing Angles and Sides in Triangles
[Free Registration/Login may be required to access all resource tools.] In this lesson students compare sides and angles in triangles. Students examine guided notes, review guided practice, watch instructional videos and attempt practice...
CK-12 Foundation
Ck 12: Geometry: Congruent Angles and Angle Bisectors
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to angles, congruent angles, and angle bisectors. Students examine guided notes, review guided practice, watch instructional videos...
Mathigon
Mathigon: Geometry: Euclidean Geometry: Definitions
This lesson focuses on Euclidean Geometry terminology; such as line, point, line segment, congruence, circle, radius, ray, and more. It defines each term and provides an example of each.
Khan Academy
Khan Academy: Use Similar and Congruent Triangles
Solve geometry problems with various triangles by using all you know about similarity and congruence. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Alabama Learning Exchange
Alex: Congruent and Similar Figures
Lesson plan where students learn about congruent and similar figures by viewing models and by using geoboards, pattern blocks, and the Internet. (Note: Lesson cited in the procedures cannot be found at the link provided.)
National Council of Teachers of Mathematics
Nctm: Illuminations: Making Triangles
Understand the mathematical meaning of a triangle and the idea of congruence, or sameness, in geometry.
Cuemath
Cuemath: Congruent Triangles
Explore the world of congruent triangles in this mini-lesson. Provides a definition and examples that help with understanding their properties. Includes a short video and practice questions with answers.
Cuemath
Cuemath: What Is Congruence?
Explore the world of congruence in this mini-lesson. Provides a definition and examples that help with understanding its properties.
Math Open Reference
Math Open Reference: Congruent Line Segments
Learn about congruent line segments with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
CK-12 Foundation
Ck 12: Interactive Geometry: 3.1 Definition of Congruence
Learn about congruence in geometry.
Quia
Ixl Learning: Congruence
Brush up on your math skills relating to congruence then try some practice problems to test your understanding.
Louisiana Department of Education
Louisiana Doe: Louisiana Believes: Eureka Math Parent Guide: Similarity
A guide to support parents as they work with their students in similarity.
Louisiana Department of Education
Louisiana Doe: Louisiana Believes: Eureka Math Parent Guide: The Concept of Congruence
A guide to support parents as they work with their students in the concept of congruence.
Other
Nearpod: Congruent Triangles & Similarity
For this lesson on congruent triangles, students explore how to use postulates to identify if triangles are congruent by SSS, SAS, ASA, and AAS.
Wolfram Research
Wolfram Math World: Congruent
This MathWorld site defines both meanings of the term congruent, also gives the commonly used notation.
Math Is Fun
Math Is Fun: Definition of Congruent
Definition of congruent. Choose the "here's more" link to see examples of a rotation, reflection and translation.
K-5 Math Teaching Resources
K 5 Math Teaching Resources: Congruent Eighths [Pdf]
This activity could be used to introduce the concept of congruence. You will need the following materials: geoboards, rubber bands, and geoboard recording paper.
Sophia Learning
Sophia: Cpctc: Lesson 2
This lesson will demonstrate the use of CPCTC in triangle congruencey proofs. It is 2 of 4 in the series titled "CPCTC."
Sophia Learning
Sophia: Reflexive Property of Congruence and Equality: Lesson 6
This lesson will introduce the reflexive property of congruence, and the reflexive property of equality. It is 6 of 6 in the series titled "Reflexive Property of Congruence and Equality."