Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Gpe, G Co, G Srt Unit Squares and Triangles

For Teachers 9th - 10th Standards
In this task, students are shown three unit squares and two line segments connecting two pairs of vertices. They are asked to find the area of a triangle formed by intersecting lines. They can solve it using coordinate geometry or...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g, G Gpe, G Srt, G Co Is This a Rectangle?

For Teachers 9th - 10th Standards
For this task, students are given four sets of coordinate pairs and are asked to determine if they represent a rectangle. Aligns with 8.G.A, 8.G.B, G-CO.B, G-GPE.B, and G-SRT.B.5.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Congruence of Alternate Interior Angles

For Teachers 8th Standards
Eighth graders are presented with a labeled drawing of two parallel lines intersected by a transversal line. They are asked to discuss congruency of angles when the picture is rotated about a point on the transversal. Aligns with 8.G.A.5.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Congruent Segments

For Teachers 8th Standards
Eighth graders are shown two line segments that are the same length and must describe a sequence of reflections that exhibits a congruence between them. Aligns with 8.G.A.2.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Congruent Triangles

For Teachers 8th Standards
In this task, 8th graders investigate congruence and transformations of two triangles on a coordinate grid. Includes a GeoGebra worksheet that the teacher can use for demonstration purposes. Aligns with 8.G.A.2.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Cutting a Rectangle Into Two Congruent Triangles

For Teachers 8th Standards
This task shows the congruence of two triangles formed by cutting a rectangle in half along the diagonal. Students are asked to investigate elements of congruence and transformations among the shapes. Aligns with 8.G.A.2.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Why Does Sss Work?

For Teachers 9th - 10th Standards
In this task, students must show that two triangles are congruent given a set of steps which produce a rigid transformation of the plane. Includes an experimental GeoGebra worksheet that instructors can use to demonstrate the task....
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Why Does Sas Work?

For Teachers 9th - 10th Standards
In this task, learners 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.
Interactive
Math Open Reference

Math Open Reference: Congruence

For Students 9th - 10th Standards
A complete reference guide to congruence including congruent triangles and polygons. It provides definitions, animation, and interactive activities that enhance further explanation.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Congruent Triangles

For Students 9th - 10th Standards
[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...
Handout
CK-12 Foundation

Ck 12: Geometry: Proofs Study Guide

For Students 9th - 10th Standards
[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).
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Congruence Statements

For Students 9th - 10th Standards
[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...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Comparing Angles and Sides in Triangles

For Students 9th - 10th Standards
[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...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Congruent Angles and Angle Bisectors

For Students 9th - 10th Standards
[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...
eBook
Mathigon

Mathigon: Geometry: Euclidean Geometry: Definitions

For Students 9th - 10th Standards
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.
Unknown Type
Khan Academy

Khan Academy: Use Similar and Congruent Triangles

For Students 9th - 10th Standards
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.
Lesson Plan
Alabama Learning Exchange

Alex: Congruent and Similar Figures

For Teachers 3rd - 5th
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.)
Interactive
National Council of Teachers of Mathematics

Nctm: Illuminations: Making Triangles

For Students Pre-K - 1st Standards
Understand the mathematical meaning of a triangle and the idea of congruence, or sameness, in geometry.
Unit Plan
Cuemath

Cuemath: Congruent Triangles

For Students 9th - 10th Standards
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.
Handout
Cuemath

Cuemath: What Is Congruence?

For Students 9th - 10th Standards
Explore the world of congruence in this mini-lesson. Provides a definition and examples that help with understanding its properties.
Handout
Math Open Reference

Math Open Reference: Congruent Line Segments

For Students 9th - 10th Standards
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.
eBook
CK-12 Foundation

Ck 12: Interactive Geometry: 3.1 Definition of Congruence

For Students 9th - 10th Standards
Learn about congruence in geometry.
Handout
Quia

Ixl Learning: Congruence

For Students 7th - 9th Standards
Brush up on your math skills relating to congruence then try some practice problems to test your understanding.
Professional Doc
Louisiana Department of Education

Louisiana Doe: Louisiana Believes: Eureka Math Parent Guide: Similarity

For Students 8th
A guide to support parents as they work with their students in similarity.