Activity
Texas Instruments

Texas Instruments: Similar Triangles and Proportions

For Teachers 9th - 10th Standards
In this activity, students will investigate the relationship among the similar triangles formed when a segment is constructed parallel to one side of a triangle. They will explore the various ratios that exist between the lengths of the...
Handout
Math Open Reference

Math Open Reference: Similar Polygons and Triangles

For Students 9th - 10th Standards
A complete reference guide to similar triangles and polygons. It provides definitions and interactive activities that enhance further explanation.
Unit Plan
Texas Education Agency

Texas Gateway: Similar Right Triangles: The Altitude to the Hypotenuse

For Students 9th - 10th
The student will apply and prove the definition of similar triangles and identify and apply the relationships that exist when an altitude is drawn to the hypotenuse of a right triangle, including the geometric mean.
Interactive
Government of Alberta

Learn Alberta: Exploring Similarity and Congruence

For Students 6th - 8th Standards
Begin by watching this captivating video showing how the concepts of similarity and congruence are found in road signs. Following the video [1:27], an interactive applet allows students to resize, flip, move and rotate triangles to...
Activity
Texas Instruments

Texas Instruments: Math Today Ballooning Inside the Box

For Teachers 9th - 10th Standards
In this activity Using the USATODAY infograph, "Ballooning inside the box", students will explore geometric relationships using similar triangles. Identifying triangles with two pairs of congruent angles to explore similarity properties...
Activity
Texas Instruments

Texas Instruments: The Tangent Ratio

For Teachers 9th - 10th Standards
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...
Whiteboard
ClassFlow

Class Flow: Ratio and Proportion Geometry Review

For Teachers 9th - 10th Standards
[Free Registration/Login Required] This flipchart is a Jeopardy style review for Ratio and Proportion. Comes form the McDougal Littell Geometry book.