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Ex 7.2, 8 - Chapter 7 Class 9 Triangles
Last updated at August 14, 2026 by Teachoo
Opposite Angles of equal sides
Chapter 7 Class 9 Triangles
Concept wise
- Congruency - Introduction
- SAS
- ASA/AAS
-
Opposite Angles of equal sides
- SSS
- RHS
- Side inequality
Transcript
Ex7.2, 8 Show that the angles of an equilateral triangle are 60 each. Given: ABC be an equilateral triangle. AB = BC = AC To prove: A = B = C = 60 Proof: AB = AC C = B Also, AC = BC B = A From (1) & (2) A = B = C In ABC, A + B + C = 180 A + A + A = 180 3 A = 180 A A A = B = C = 60 Hence proved
