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.
CK-12 Foundation
Ck 12: Geometry: 30 60 90 Right Triangles Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept teaches students about the 30-60-90 special right triangle and how to apply its properties.
CK-12 Foundation
Ck 12: Geometry: Self Similarity Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide looks at several examples of self-similarity.
Texas Instruments
Texas Instruments: Real Life Real World Activity Forestry
Forest industry professionals make measurements in their work using tools including the Clinometer and the Biltmore Stick. These tools are based on the concepts of similar triangles and trigonometric ratios in a right triangle. This...
CK-12 Foundation
Ck 12: Geometry: Self Similarity
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to self-similarity and presents several common examples of self-similarity.
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: Geometry: Sas Similarity
[Free Registration/Login may be required to access all resource tools.] Use the SAS Similarity Theorem to determine if triangles are similar.
CK-12 Foundation
Ck 12: Geometry: Parallel Lines and Transversals
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to use the Triangle Proportionality Theorem with multiple parallel lines.
Mathigon
Mathigon: Geometry: Triangles and Trigonometry: Introduction
This lesson is an introduction to triangles and trigonometry by looking at the history of mapping and specifically, measuring the height of a mountain.
Sonoma State University
Sonoma State University: Parallel Lines and Similar and Congruent Triangles
This site defines parallel lines, parallel lines cut by a transverse, and congruent triangles. It also contains links for related terms.
TeachEngineering
Teach Engineering: You've Got Triangles!
Students learn about trigonometry, geometry and measurements while participating in a hands-on interaction with LEGO MINDSTORMS NXT technology. First they review fundamental geometrical and trigonometric concepts. Then, they estimate the...
AAA Math
Aaa Math: Geometry
A comprehensive tutorial from AAA Math that contains explanations, interactive practices and challenging games.
CK-12 Foundation
Ck 12: Indirect Measurement
[Free Registration/Login Required] Students use similar triangles to determine the height of the base of a tree house. Click learn more to watch a video and click challenge me to answer a practice question.
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...
Alabama Learning Exchange
Alex: How Tall Is the School's Flagpole?
The purpose of this activity is to help students apply math concepts concerning similar triangles and trigonometric functions to real life situations. The students learn how to take these concepts and use them to find measurements of...
University of Cambridge
University of Cambridge: Maths and Sports: Stadium Sightline
How would you design the seating for an Olympic stadium to give spectators the best view of events? This geometry and modelling activity is designed to be accessible to both GCSE and A-level maths students (Key Stage 4 and Key Stage 5),...
Cuemath
Cuemath: Pythagoras Theorem
In this lesson, you will learn about the Pythagoras theorem, its derivations, and equations followed by solved real-world problems on the Pythagoras theorem triangle and squares.
CK-12 Foundation
Ck 12: Geometry: Parallel Lines and Transversals
[Free Registration/Login may be required to access all resource tools.] Apply the fact that transversals cut parallel lines proportionally.
ClassFlow
Class Flow: Ratio and Proportion Geometry Review
[Free Registration/Login Required] This flipchart is a Jeopardy style review for Ratio and Proportion. Comes form the McDougal Littell Geometry book.
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.
Texas Instruments
Texas Instruments: The Tangent Ratio
In this activity students explore the tangent ratio. Students construct a right triangle using perpendicular lines, and a line that forms the hypotenuse of the triangle. When students construct the hypotenuse line it is very important...