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Question
In the given below fig. ABCD, ABFE and CDEF are parallelograms. Prove that ar (ΔADE)
= ar (ΔBCF)

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Solution
Given that,
ABCDis a parallelogram ⇒ AD = BC
CDEF is a parallelogram ⇒ DE = CF
ABFE is a parallelogram ⇒ AE = BF
Thus, in Δs ADE and BCF,we have
AD = BC,DE = CF and AE = BF
So, by SSS criterion of congruence, we have
ΔADE ≅ ΔABCF
∴ ar ( Δ ADE ) = ar ( BCF )
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