Theorem 8.1 - Chapter 8 Class 9 Quadrilaterals

Last updated at August 5, 2026 by

Theorem 8.1 - Class 9 - Diagonal of a parallelogram divides - Theorems

part 2 - Theorem 8.1 - Theorems - Serial order wise - Chapter 8 Class 9 Quadrilaterals

 

 

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Theorem 8.1: A diagonal of a parallelogram divides it into two congruent triangles Given: A parallelogram ABCD with AC as its diagonal To prove: ΔABC ≅ ΔADC Proof: Opposite sides of parallelogram is parallel So, AB ∥ DC and AD‖∥ BC In Δ ABC & Δ ADC ∠ BAC = ∠ DCA AC = AC ∠ DAC = ∠ BCA ∴ ΔABC ≅ ΔADC Hence proved

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