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3.6: Similar Triangles

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    Definitions and Theorems

    Definition: Congruent Triangles

    Two triangles are said to be congruent if their corresponding angles are equal, and their corresponding sides have the same lengths. Symbolically, we use the congruency symbol \( \cong \) to state that two triangles are congruent.

    Definition: Similar Triangles

    Two triangles are similar if their corresponding angles are equal.

    Theorem: Similarity Conditions for Triangles

    Two triangles are similar if either their corresponding angles are equal or their corresponding sides are proportional.


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