Scholastic
Scholastic: Study Jams! Math: Geometry: Congruent Figures
Explore step by step how to determine if figures are congruent?
Khan Academy
Khan Academy: Find Angles in Congruent Triangles
Given two triangles, determine whether they are congruent and use that to find missing angle measures. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.3 Aa Triangle Similarity
If two triangles are similar, it means that all corresponding angle pairs are congruent and all corresponding sides are proportional. However, in order to be sure that two triangles are similar, you do not necessarily need to have...
Varsity Tutors
Varsity Tutors: Hotmath: Similar Figures
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.
Science Struck
Science Struck: Similarity Statement in Geometry With Examples
Models how to write a similarity statement about different types of triangles and quadrilaterals.
Geometry Help
Geometry Help: Similar Triangles
Explains the basic concept of similar triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.7 Applications of Similar Triangles
Learn how similar triangles have congruent corresponding angles and proportional corresponding sides.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.5 Sss Triangle Similarity
Explore and understand two triangles that are similar.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.4 Sas Triangle Similarity
Explore and understand triangle similarity.
Khan Academy
Khan Academy: Solve Similar Triangles (Basic)
Given two similar triangles and some of their side lengths, find a missing side length. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Solve Similar Triangles (Advanced)
Given two similar triangles and some of their side lengths, find a missing side length. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Sophia Learning
Sophia: Similarity
This learning tutorial describes the characteristics of similar figures and how to use scale factor and proportions to determine missing side lengths. The lesson includes PowerPoint presentations and videos demonstrating how to solve...
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.)
Illustrative Mathematics
Illustrative Mathematics: G Gpe, G Co, G Srt Unit Squares and Triangles
In this task, young scholars 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...
Texas Instruments
Texas Instruments: Similar Figures Discovery Activity
Students can use Cabri Jr. to discover two properties of similar triangles: corresponding angles are congruent and corresponding sides are proportional.
Math Open Reference
Math Open Reference: Similar Triangles
Learn about similar triangles with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Shodor Education Foundation
Shodor Interactivate: Lesson: Translations, Reflections, and Rotations
This upper elementary and middle school lesson plan introduces a variety of motion geometry concepts such as translations, reflections, and rotations. Lots of interactive support for students.
Khan Academy
Khan Academy: Congruence and Transformations
Given a pair of figures in the coordinate plane, try to map one onto the other and determine whether they are congruent. Includes examples of glide reflections. Students receive immediate feedback and have the opportunity to try...
Rice University
Rice University: Cynthia Lanius: Polyominoes Fun With Dominoes
For students who have ever played dominoes and Tetris, polyominoes will strike them as a great deal of fun. Teachers will see the educational benefits of working with similar and congruent shapes and rotating them in a plane. Exploration...
CK-12 Foundation
Ck 12: Geometry: Similar Polygons and Scale Factors
[Free Registration/Login may be required to access all resource tools.] Apply the properties of similar polygons.
CK-12 Foundation
Ck 12: Geometry: Similar Polygons and Scale Factors
[Free Registration/Login may be required to access all resource tools.] This concept teaches students what similar polygons are and how to use scale factors to solve for missing information in similar polygons.
CK-12 Foundation
Ck 12: Geometry: Perimeter and Area Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide looks at the definitions and units for perimeter, area, and circumference, and at the perimeter and area of different shapes, including regular...
The Math League
The Math League: Similar Figures
This tutorial explains what similar figures are in geometry and provides examples.
Illustrative Mathematics
Illustrative Mathematics: 8.g, G Gpe, G Srt, G Co Is This a Rectangle?
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.