[Free Registration/Login may be required to access all resource tools.] Provides an overview of triangle congruence, including key terms, properties of congruent triangles, triangle postulates and theorems, and special triangles.

See how two triangles are congruent it means that all corresponding angle pairs and all corresponding sides are congruent.

Dr. Math responds to a question about how to determine if two triangles are similar. The Dr. goes into detail about the process and gives several examples that are worked out for you.

Contains relevant information regarding the Pascal's Triangle "Inform the students that the rows and columns of integers that make up the triangle known as "Pascal's Triangle" contain many number patterns that they can easily recognize...

Given two congruent triangles, students are asked to analyze the effects of different transformations. Aligns with G-CO.A.5.

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.

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.

In this lesson, students will participate in discussions and activities that will have them explore the number patterns and fractal properties of Pascal's Triangle.

Solve word problems that involve general triangles using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Here are five triangle problems to solve using the Law of Sines, Law of Cosines, Pythagorean Theorem, and trigonometry. All problems have detailed written solutions included.

Suppose we are given a circle of radius r. The goal of this task is to construct an equilateral triangle whose three vertices lie on the circle. Aligns with G-CO.D.13.

Given an equilateral triangle, learners are asked to explore its symmetries using rigid transformations of the plane. Aligns with G-CO.B.

Each calculation option has sub-bullets that list the sequence of methods used in this calculator to solve for unknown angle and side values including Sum of Angles in a Triangle, Law of Sines, and Law of Cosines.

In this task, students must decide where to place sprinklers on a lawn so that the maximum area of the lawn will be watered. To solve it, they must find areas of sectors of circles and use trigonometric ratios to solve right triangles....

In this inquiry-based lesson, young scholars will work in groups to gather measurements needed to approximate the height of a building. Students will discover how geometric mean can be used to find the lengths of missing sides of right...

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.

The purpose of this task is to use similar triangles and setting up a proportion in order to calculate a side length. Aligns with G-SRT.B.5.

The purpose of this task is to prove the Pythagorean Theorem using similar triangles. Aligns with G-SRT.B.4.

This task has young scholars link their intuitive notions of symmetries of a triangle with statements proving that said triangle is unmoved by applying certain rigid transformations. The mechanism through which students do this is via...

In this task, learners investigate polynomial identities in order to generate Pythagorean triples. Aligns with A-APR.C.4.

Explore the world of the Law of Cosine in this mini-lesson. Provides a definition, simulations, examples, and practice questions that help with understanding.

Demonstrates how to use trig ratios to do simple solving of triangles.

Students learn abouT the Law of Reflection by constructing an equilateral triangle using graph paper, pencil, protractor, and a ruler and a "laser triangle" using a laser pointer and front-silvered mirrors.

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...