Triangle Congruence Criteria
Proving triangles are congruent using SSS, SAS, ASA, and AAS criteria.
Key Questions
- Justify why AAA is not a valid criterion for triangle congruence.
- Assess the minimum amount of information needed to fix a triangle's shape.
- Analyze how congruence proofs are used in structural engineering.
Common Core State Standards
Suggested Methodologies
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Planning templates for Mathematics
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.
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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.
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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.
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