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Unit Plan
CK-12 Foundation

Ck 12: Congruent Triangles

For Students 5th - 9th Standards
[Free Registration/Login Required] Students explore the concept of congruent triangles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about...
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Unit Plan
CK-12 Foundation

Ck 12: Congruence Statements

For Students 9th - 10th Standards
[Free Registration/Login Required] Students explore the concept of congruence statements by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about...
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Activity
Texas Instruments

Texas Instruments: Properties of Parallelograms

For Teachers 9th - 10th Standards
In this activity, you will construct the geometric object by following the instructions below, and then answer the questions about the object.
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Handout
Varsity Tutors

Varsity Tutors: Hotmath: Similar Figures

For Students 9th - 10th Standards
Find a clear explanation of similar figures. Discusses how they can be transformed through a sequence of rotations, reflections, translations, and dilations. Explanations are supported with illustrated examples.
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Unit Plan
Mathigon

Mathigon: Geometry: Rigid Transformations

For Students 9th - 10th Standards
This lesson focuses on rigid transformations, a specific set of rules that convert one geometric figure into another one. There are many different types of transformations, like reflections or rotations. It provides several practice...
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: g.co Reflections and Isosceles Triangles

For Teachers 9th - 10th Standards
This task has students link their intuitive notions of symmetries of a triangle with statements proving that said triangle is unmoved by applying certain rigid transformations. The mechanism through which students do this is via...
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Properties of Congruent Triangles

For Teachers 9th - 10th Standards
The goal of this task is to understand how congruence of triangles, defined in terms of rigid motions, relates to the corresponding sides and angles of triangles. Aligns with G-CO.B.7.
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Building a Tile Pattern by Reflecting Hexagons

For Teachers 9th - 10th Standards
This task applies reflections to a regular hexagon to construct a pattern of six hexagons enclosing a seventh. The focus of the task is on using the properties of reflections to deduce this seven-hexagon pattern. Aligns with G-CO.B.6.
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Building a Tile Pattern by Reflecting Octagons

For Teachers 9th - 10th Standards
This task applies reflections to a regular octagon to construct a pattern of four octagons enclosing a quadrilateral. The focus of the task is on using the properties of reflections to deduce that the quadrilateral is actually a square....
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Showing a Triangle Congruence: The General Case

For Teachers 9th - 10th Standards
Given distinct, congruent triangles, young scholars are asked to show that congruence can always be shown with one, two, or three rigid motions. Aligns with G-CO.A.5.
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Showing a Triangle Congruence: A Particular Case

For Teachers 9th - 10th Standards
Given two congruent triangles, students are asked to analyze the effects of different transformations. Aligns with G-CO.A.5.
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eBook
Mathigon

Mathigon: Euclidean Geometry: Introduction

For Students 9th - 10th Standards
Mathematicians in ancient Greece were amazed by mathematical patterns, and wanted to explore and explain them. They began to study mathematics just "for fun" without a specific application in mind. One of these mathematicians, Thales of...
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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....
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Interactive
Other

Desmos: Geometry Scavenger Hunt

For Students 9th - 10th Standards
Use the Desmos transformation tools (link at top of page) to complete this scavenger hunt. There are three levels to choose from and solutions are included.
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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.
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Activity
Analyze Math

Analyze Math: Congruent Triangle Examples

For Students 9th - 10th Standards
The geometry tutorial investigates congruent triangles. Students learn about the definitions and theorems on congruent triangles. Some topics included are angle-side-angle, side-side-side, and side-angle-side congruence postulates. The...
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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...
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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.] This concept teaches students what it means for two triangles to be congruent and how to identify corresponding parts of congruent triangles. Students examine guided...
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Handout
CK-12 Foundation

Ck 12: Geometry: Types of Transformations Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Transformations move and modify geometric shapes. There are several types of transformations that all transform figures in different ways. These transformations can...
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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...
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Geometric Translations

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson, students learn how to translate a figure. They examine guided notes, review examples, watch instructional videos, and try practice problems.
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Lesson Plan
Alabama Learning Exchange

Alex: Geometrica Fights Back!

For Teachers 9th - 10th Standards
This activity is designed to give students practice with the properties of special quadrilaterals (parallelograms, rectangles, rhombuses, squares, trapezoids, and kites). The students are provided with a "murder mystery" sheet with...
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Handout
Geometry Help

Geometry Help: Rhombus

For Students 9th - 10th Standards
Explains the basic concept of a rhombus with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
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Handout
Geometry Help

Geometry Help: Parallelograms

For Students 9th - 10th Standards
Explains the basic concept of parallelograms with step-by-step instructions and methods for solving specific problems on your own relating to this topic.