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...

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...

Provides examples that illustrate similar triangles.

Understand the mathematical meaning of a triangle and the idea of congruence, or sameness, in geometry.

The goal of this task is to examine similarity of triangles from the point of view of proportional sides, showing that this is sufficient to conclude that two triangles are similar. Aligns with HSG-SRT.A.2.

This task works toward establishing the AA criterion for similarity of triangles. Young scholars are asked to provide a detailed sequence of transformations that moves one of the given triangles onto the other. Aligns with G-SRT.A.3.

The goal of this task is to use similarity transformations to relate two triangles. The triangles are obtained by taking midpoints of two sides of a given triangle. Aligns with HSG-CO.C.10.

Given a picture of a triangle on a coordinate grid, students are asked to find the coordinates of points which divide line segments in a given ratio. Aligns with G-GPE.B.6 and G-SRT.B.5.

The purpose of this task is to use the notion of similarity to define the sine and cosine of an acute angle. Aligns with G-SRT.C.6.

The goal of this task is to use similar triangles to establish the slope criterion for perpendicular lines. Aligns with HSG-GPE.B.5 and HSG-SRT.B.5.

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.

For this task, students are asked to make a mathematical model and determine if it is possible to see a point on the surface of the Earth that is 85 miles away, and well below sea level, from the top of a mountain. The curvature of the...

A phenomenal growth of land trusts or conservancies, similar in focus to the Nature Conservancy began to occur statewide beginning in the mid-1980s. For instance, the Triangle Land Conservancy was established in 1983 to support native...

Print or create worksheets to assess students' understanding of the connections between proportional relationships, lines, and linear equations.