CBSE Class 9CBSE
Share
Notifications

View all notifications

Properties of a Parallelogram - In a Parallelogram, Opposite Sides Are Equal. Ab = Cd and Bc = Da

Login
Create free account


      Forgot password?

theorem

Theorem: In a parallelogram, opposite sides are equal. 
AB = CD and BC = DA
Proof: Let AC be the diagonal of parallelogram. consider two ∆ABC and ∆ CDA
∠CAB = ∠ACD ....(1)  (Alternate interior angles)
∠ACB =∠ CAD  ...(2) (Alternate interior angles)
And , AC = CA ...(3) (common side)
From condition 1,2 and 3 
∆ABC ≅  ∆ CDA (By ASA congruence rule) 
Hence as triangles are congruent triangles, the corresponding sides are equal,
So , AB = CD (C.P.C.T)
BC = DA (C.P.C.T)

Shaalaa.com | Theorem: In a parallelogram, opposite sides are equal.

Shaalaa.com


Next video


Shaalaa.com


Theorem: In a parallelogram, opposite sides are equal. [00:10:24]
S
Series 1: playing of 1
0%


S
View in app×