Triangle Similarity & Proportions

learning_notes

Last updated: 8/16/2025

Key Concepts:

  • Similar Triangles Definition – Two triangles are similar if their corresponding angles are equal and their corresponding sides are proportional.
  • Triangle Similarity Theorem:
    • AA (Angle-Angle) – Two angles of one triangle match two angles of another.
    • SSS (Side-Side-Side) – All three sides of two triangles are proportional.
    • SAS (Side-Angle-Side) – Two corresponding sides of two triangles are proportional and their included angle match.

Skills Covered:

  • Identifying similar triangles using triangle similarity theorem.
  • Setting up and solving proportions to find missing side lengths.
  • Applying similar triangle properties to real-world problems (e.g., shadow length, building height, breaking down a quadrilateral into triangles for easier calculations).

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