Geometers prove that triangle PQR is congruent to triangle ABC by describing any combination of rotations, reflections, and translations that would prove it so. There is only this single task on the handout, but a detailed explanation of...

The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...

High schoolers identify properties of triangles. In this geometry lesson plan, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.

Students investigate triangles and congruences. In this geometry lesson, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.

Students investigate triangles and their properties. For this geometry lesson, students differentiate between similar and congruent triangles. They use the SSS theorem to help identify the triangles that are similar or congruent.

Students examine Triangle Congruency. In this measurement comparison lesson, students use inductive, deductive and analytical thinking skills to prove triangle congruency. Students analyze and record their findings on activity worksheets.

Students find triangles in the real world. In this geometry lesson, students analyze and identify properties of two and three-dimensional objects. They differentiate between similarity and congruence.

Young scholars investigate properties of circles. In this geometry activity, students differentiate between similarity and congruence as they observe polygons. They investigate properties of two and three dimensional shape.

Students differentiate between similarity and congruence using polygons. In this geometry lesson, students label triangles based on their properties. They find missing sides and angles using the interior sum theorem.

Young scholars identify the properties of solids and polygons. In this geometry instructional activity, students identify the different measurements of a triangle. They use congruence parts and theorem to prove their answer.

Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...

Learners discuss and review examples of the Pythagorean Theorem using a GSP, Geometer's Sketchpad, activity.

Learners investigate special segments in triangles. For this geometry lesson, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.

Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...

Young geometers apply their deductive reasoning skills and knowledge of proving triangles congruent in a task that asks them to prove if a point lies on the perpendicular bisector of a segment, then it is equidistant from the endpoints...

Students identify and use the similarity theorem. In this geometry lesson plan, students differentiate between congruent and similar triangles. They solve problems using the computer modifying shapes by dragging.

This task asks learners to prove that the segment joining the midpoints of two sides of a parallelogram is both congruent and parallel to an adjacent side of the parallelogram. The activity would be good to use in a discussion about how...

Students investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, students discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by two rays...

High schoolers identify triangles as similar or congruent. In this geometry lesson, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and...

Students investigate the relationship between angles and their sides. In this geometry lesson, students prove why SSA does not work as a true angle side relationship theorem.

Students model the geometric relationship with graphing. In this geometry lesson, students differentiate between parallel, perpendicular, similar and congruent shapes. They use properties of polygons to differentiate their shapes...