Congruency - Congruent Triangles
Congruent triangles are identical in shape and size, with matching sides and angles, proven using specific congruency rules.
Core concept
Two triangles are congruent if all corresponding sides and angles are equal, meaning one can perfectly overlap the other.
How it works
The SSS (Side-Side-Side) rule proves congruency if all three sides of one triangle equal all three sides of another.
Why it matters
The SAS (Side-Angle-Side) rule proves congruency if two sides and the included angle match between triangles.
Key detail
Understanding congruency helps us prove geometric relationships and is fundamental for more advanced geometry topics.
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Quick notes
• Congruent triangles are identical in shape and size.
• All corresponding sides and angles match.
• One triangle can perfectly overlap the other.
• SSS rule: all three sides equal.
• SAS rule: two sides and included angle equal.
• These rules prove congruency.
• Congruency helps prove geometric relationships.
• It's fundamental for advanced geometry.