Rigid Motions in the Plane
Mathematics · 10th Grade · Transformations and Congruence · Weeks 10-18

Rigid Motions in the Plane

Defining congruence through the lenses of translations, reflections, and rotations.

Common Core State StandardsCCSS.Math.Content.HSG.CO.A.2CCSS.Math.Content.HSG.CO.B.6

About This Topic

Defining congruence through the lenses of translations, reflections, and rotations.

Key Questions

  1. Differentiate which properties of a figure remain invariant under a reflection versus a translation.
  2. Explain how any congruence can be described as a sequence of rigid motions.
  3. Justify why we define congruence through motion rather than just measurement.

Active Learning Ideas

See all activities→

Activities & Teaching Strategies

See all activities

Planning templates for Mathematics

Lesson Plan

5E Model

The 5E Model structures lessons through five phases (Engage, Explore, Explain, Elaborate, and Evaluate), guiding students from curiosity to deep understanding through inquiry-based learning.

Unit Planner

Math Unit

Plan a multi-week math unit with conceptual coherence: from building number sense and procedural fluency to applying skills in context and developing mathematical reasoning across a connected sequence of lessons.

Rubric

Math Rubric

Build a math rubric that assesses problem-solving, mathematical reasoning, and communication alongside procedural accuracy, giving students feedback on how they think, not just whether they got the right answer.

More in Transformations and Congruence

Dilations and Non-Rigid Transformations

Students will explore dilations and other non-rigid transformations, understanding their effect on size and shape.

2 methodologies

Symmetry in Geometric Figures

Students will identify and describe lines of symmetry and rotational symmetry in various two-dimensional figures.

2 methodologies

Triangle Congruence Criteria

Establishing the minimum requirements for proving two triangles are identical.

2 methodologies

Proving Triangle Congruence

Students will apply SSS, SAS, ASA, AAS, and HL congruence postulates to write formal proofs.

2 methodologies

Isosceles and Equilateral Triangles

Students will explore the properties of isosceles and equilateral triangles and use them in proofs and problem-solving.

2 methodologies

Properties of Quadrilaterals

Classifying four-sided figures based on their symmetry, side lengths, and angle properties.

3 methodologies