Khan Academy
Khan Academy: Triangle Similarity Review
Review the triangle similarity criteria and use them to determine similar triangles.
CK-12 Foundation
Ck 12: Geometry: Aa Similarity
[Free Registration/Login may be required to access all resource tools.] Use the AA Similarity Postulate to determine if triangles are similar.
CK-12 Foundation
Ck 12: Geometry: Aa Similarity (Intermediate)
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to identify whether or not two triangles are similar using AA Similarity.
CK-12 Foundation
Ck 12: Geometry: Sss Similarity
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to decide whether or not two triangles are similar using SSS Similarity.
CK-12 Foundation
Ck 12: Geometry: Sas Similarity
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to decide whether or not two triangles are similar using SAS Similarity.
Khan Academy
Khan Academy: Practice: Determine Similar Triangles: Sss
In this set of questions, students practice identifying side-side-side similarity among triangles. Includes hints.
CK-12 Foundation
Ck 12: Geometry: Indirect Measurement
[Free Registration/Login may be required to access all resource tools.] In this lesson students use similar triangles and proportions to find measurements indirectly. Students examine guided notes, review guided practice, watch...
Mangahigh
Mangahigh: Shape: Solve Problems With Similar Shapes
Test your knowledge of similar triangles and shapes.
PBS
Pbs Learning Media: Triangles
In this video segment [2:01] from Cyberchase, the CyberSquad finds that by arranging triangle tiles they are able to create a path that will allow them to cross a river of hot lava.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.6 Theorems Involving Similarity
Learn the many theorems about triangles that you can prove using similar triangles.
University of Saskatchewan (Canada)
University of Saskatchewan: Triangles
This site from the University of Saskatchewan provides an explanation of similar triangles, the Pythagorean theorem, and the distance between arbitrary points in a plane. Example problems for each of these concepts are provided.
Cuemath
Cuemath: Median of a Triangle
This lesson explores the equation of the median of a triangle formula, sum of medians of a triangle, altitude of a triangle, median of equilateral triangle formula, and median of a triangle definition while discovering the interesting...
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.
Science Struck
Science Struck: Similarity Statement in Geometry With Examples
Models how to write a similarity statement about different types of triangles and quadrilaterals.
CK-12 Foundation
Ck 12: Geometry: Sss Similarity
[Free Registration/Login may be required to access all resource tools.] Use the SSS Similarity Theorem to determine if triangles are similar.
Illustrative Mathematics
Illustrative Mathematics: G Gpe, G Co, G Srt Unit Squares and Triangles
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...
Khan Academy
Khan Academy: Use Similar & Congruent Triangles
Solve geometry problems with various polygons by using all you know about similarity and congruence.
Khan Academy
Khan Academy: Solve Triangles: Angle Bisector Theorem
Use the Angle Bisector Theorem to find missing side lengths in triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Geometry: Indirect Measurement
[Free Registration/Login may be required to access all resource tools.] Recognize similarity and use similar figures to solve problems by using indirect measurement
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.
CK-12 Foundation
Ck 12: Geometry: Polygon Similarity Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide looks at similar polygons, scale factor (ratio), and triangle similarity.
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...
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.