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### We found 110 resources with the concept geometric proofs

EngageNY

#### Comparing the Ratio Method with the Parallel Method

Can you prove it? Lead your class through the development of the Side Splitter Theorem through proofs. Individuals connect the ratio and parallel method of dilation through an exploration of two proofs. After completing the proofs,...

EngageNY

#### End-of-Module Assessment Task - Geometry (module 1)

Have you hit a wall when trying to create performance task questions? Several open-ended response questions require a deep level of thinking. Topics include triangle congruence, quadrilaterals, special segments, constructions, and...

EngageNY

#### Review of the Assumptions (part 2)

Is the amount of information getting overwhelming for your geometry classes? Use this strategy as a way to organize information. The resource provides a handout of information studied in relation to triangle congruence. It includes a...

EngageNY

#### Special Lines in Triangles (part 2)

Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...

EngageNY

#### Review of the Assumptions (part 1)

What was the property again? Tired of hearing this from your pupils? Use this table to organize properties studied and as a reference tool for individuals. Learners apply each property in the third column of the table to ensure their...

EngageNY

#### Triangle Congruency Proofs (part 2)

Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...

EngageNY

#### Triangle Congruency Proofs (part 1)

Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...

EngageNY

#### Congruence Criteria for Triangles—ASA and SSS

How do you know if a pair of triangles are congruent? Use the lesson to help class members become comfortable identifying the congruence criteria. They begin with an exploration of ASA and SSS criteria through transformations and...

EngageNY

#### Congruence Criteria for Triangles—SAS

Looking for a different approach to triangle congruence criteria? Employ transformations to determine congruent triangles. Learners list the transformations required to map one triangle to the next. They learn to identify congruence if...

EngageNY

#### Looking More Carefully at Parallel Lines

Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...

Lesson Planet

#### Geometry Project

Proofs are usually an intimidating assignment. An engaging lesson focused on geometric proofs may reduce the anxiety! Pupils choose between several triangle proofs to complete and work on completing them. The assignment also gives a...

Lesson Planet

#### Postulates and Proofs: Let's take it to the courtroom!

Order in the court! Turn your geometry classroom into a courtroom and have your pupils defend their proofs. A fun and educational lesson allows both individual and group work with geometric proofs and group presentations in a court of...

Lesson Planet

#### Analytic Geometry Study Guide

Are you looking for a comprehensive review that addresses the Common Core standards for geometry? This is it! Instruction and practice problems built specifically for standards are included. The material includes geometry topics from...

Lesson Planet

#### Are They Similar?

Learners separate things that just appear similar from those that are actually similar. A diagram of triangles is given, and then a variety of geometric characteristics changed and the similarity of the triangles analyzed. Because the...

Lesson Planet

#### Similar Triangles

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...

Lesson Planet

#### Shortest Line Segment from a Point P to a Line L

One of the hardest skills for many young geometers to grasp is to move beyond just declaring obvious things true, and really returning to fundamental principles for proof. This brief exercise stretches those proving muscles as the class...

Lesson Planet

#### Accelerated Geometry Review Sheet

Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...

Lesson Planet

#### Vertical Angles Proof Samples

This visual, manipulative-based format for teaching geometric proofs nicely scafolds learners' development of mathematical reasoning and proof skills. This sample represents a proof of the congruence of vertical angles in four formats;...

Lesson Planet

#### The Parallelogram Law

Use your pupils' sense of curiosity to explore the Parallelogram Law. Here is an activity that outlines a complete instructional activity from beginning to end, allowing pupils to follow a conjecture through to the proof stage.

Lesson Planet

#### Semester 1 Review for Geometry final

In this geometry worksheet, 10th graders solve problems that are based on the topics covered in a first semester geometry class, including, linear equations and the equations of parallel and perpendicular lines, the logic of geometry,...

Lesson Planet

#### Proving Quadrilateral Properties

Working backwards can sometimes help you see a path to solving a problem. In this chapter, properites of quadrilaterials are proven by looking at flowcharts and working the probem backwards. Worked through examples are given, along with...

Lesson Planet

#### Proving Supplementary and Complementary

Learners examine their prior knowledge of algebra to explore geometric proof. In this proving supplementary and complementary instructional activity, students prove a solution to an equation using algebraic properties. Learners then...

Lesson Planet

#### Geometry: Properties of Triangles

In this properties of triangles instructional activity, students use their knowledge of triangles to find determine angle measurement. They use geometric theorems to prove equal angles. This three-page instructional activity contains 15...

Lesson Planet

#### Parallelograms

In this parallelograms worksheet, 10th graders solve and measure 81 various types of problems that include parallelograms. First, they use the figure shown to solve each of the angle measurements listed. Then, students explain why other...