Theorems

Theorem 6.1

Theorem 6.6

Theorem 6.2 Important Deleted for CBSE Board 2025 Exams You are here

Theorem 6.3 Deleted for CBSE Board 2025 Exams

Theorem 6.4 Deleted for CBSE Board 2025 Exams

Theorem 6.5 Important Deleted for CBSE Board 2025 Exams

Theorem 6.7 Important Deleted for CBSE Board 2025 Exams

Theorem 6.8 Deleted for CBSE Board 2025 Exams

Chapter 6 Class 9 Lines and Angles

Serial order wise

Last updated at April 16, 2024 by Teachoo

Theorem 6.2 :- If a transversal intersects two parallel lines, then each pair of alternate interior angles are equal. Given :- Two parallel lines AB and CD. Let PS be the transversal intersecting AB at Q and CD at R. To Prove :- Each pair of alternate interior angles are equal. i.e, BQR = CRQ and AQR = QRD Proof :- First, we will prove BQR = CRQ From (1) and (2) BQR = CRQ Similarly we can prove AQR = QRD Hence, pair of alternate interior angles are equal. Hence proved.