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Theorems

Theorem 6.1

Theorem 6.2 Important Deleted for CBSE Board 2023 Exams

Theorem 6.3 Deleted for CBSE Board 2023 Exams

Theorem 6.4 Deleted for CBSE Board 2023 Exams

Theorem 6.5 Important Deleted for CBSE Board 2023 Exams

Theorem 6.6

Theorem 6.7 Important Deleted for CBSE Board 2023 Exams You are here

Theorem 6.8 Deleted for CBSE Board 2023 Exams

Last updated at Aug. 24, 2021 by Teachoo

Theorem 6.7 :- The sum of all angles are triangle is 180°. Given :- Δ PQR with angles ∠1, ∠2 and ∠3 Prove :- ∠1 + ∠2 + ∠3 = 180° Construction:- Draw a line XY passing through P parallel to QR Proof: Also, for line XY ∠1 + ∠4 + ∠5 = 180° ∠1 + ∠2 + ∠3 = 180° Hence, sum of all angle of a triangles are equal. Hence proved