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It is a quadrilateral where

both pairs of opposite sides are parallel

i.e. AB ∥ DC and AD ∥ BC

 

Properties of Parallelogram:

  1. Opposite sides are equal
    AB = CD & AD = BC

  2. Opposite angles are equal
    ∠A = ∠C and ∠B = ∠D

  3. Adjacent angles are supplementary

      ∠A + ∠B = 180°

      ∠A + ∠D = 180° 

      ∠C + ∠D = 180°    

      ∠B + ∠C = 180°
    18.jpg

  4. Diagonals bisect each other

    AO = CO and BO = DO

Proof : Class 9 th Chapter 8 Theorem 8.6

     5.Diagonals divides the Parallelogram into two congruent triangles

       ∆ ABC ≅ ∆ CDA and 

       ∆ BAD ≅ ∆ DCB

Proof : Class 9 th Chapter 8 Theorem 8.1

  1. Chapter 3 Class 8 Understanding Quadrilaterals
  2. Concept wise
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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.