While it may seem incredibly obvious to the geometry student that congruent sides make congruent triangles, the proving of this by definition actually takes a bit of work. This exercise steps the class through this kind of proof by...

In the activity on this webpage, learners use interactive graphing technology to investigate transformations of graphs. In the first part of the task, they look at the graph of a quadratic function with coordinates of a few points...

Bank on geometry to line up the shot. The resource asks the class to determine the location to bank a cue ball in a game of billiards. Using their knowledge, class members determine where to hit the bumper to make a shot and discuss...

Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...

Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.

Given a pair of parallel lines and a triangle in between, geometers prove that the sum of the interior angles is 180 degrees. This quick quest can be used as a pop quiz or exit ticket for your geometry class.

Explore the mathematics of the paper snowflake! During the five lessons progressing in complexity from K through 12, pupils use spatial geometry to make predictions. Scholars consider a folded piece of paper with shapes cut out....

A triangle rests in quadrant two, from which your class members must draw reflections, both over x=2 and x=-2. This focused exercise strengthens students' skills when it comes to reflection on the coordinate plane.

Young mathematicians investigate the use of symmetry in graphic design. After first learning about reflection, translational, and rotational symmetry, children use this new knowledge to identify symmetry in letters of the...

Just about every public building that your students are familiar with has an access ramp which complies with ADA requirements. As it turns out, designing such a ramp is an excellent activity to incorporate slope, the Pythagorean Theorem,...

Your Geometry learners will collaboratively prove that the tangent line of a circle is perpendicular to the radius of the circle. A deliberately sparse introduction allows for a variety of approaches to find a solution. 

Your geometry learners explore Angle-Side-Angle congruence in this collaborative task. The sum of the interior angles of all triangles being one hundred eighty degrees, is the key learners will discover as they explain their reasoning...

Learners investigate the symmetries of a convex quadrilateral in a collaborative activity. Rigid motion and complements are explored as learners analyze different cases of reflections across a line.

Geometers explore symmetries of isosceles triangles by using rigid transformations of the plane. They complete four tasks, including congruence proofs, which illustrate the relationship between congruence and rigid transformations. The...

In this activity the teacher will send two lists, a window range, and an educational document via the TI-Navigator. Students will explore the reflections and rotations of a shape in the rectangular coordinate system.

Compose equivalent transformations in two different ways.

A unique geometry project that asks students to complete a transformation using a picture. Project includes instructions, examples, and quiz questions.

Twenty-five problems cover the various transformational geometry topics in different settings. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View...

In this activity, students study different types of transformations.

Practice using your graphing calculator for Geometry problems. If you get stumped or if you would like to check your work, then select the View Solution button, which is located directly under each problem.

In this activity, students describe how to move a shape from one place to another in a plane. They learn about translations, rotations, and line reflections. [Requires Adobe Reader.]

In this activity, students will explore the properties of rotations and the relationships between the original and image figures.

It is important for students to know what happens to the coordinates of points when they are translated in the coordinate plane. This activity enables students to use Cabri Jr. to develop this understanding.

Using Cabri Jr. and the properties of rotations to get a true understanding of how a figure is rotated about a point.