Q1 of 49 Page 26

Select the appropriate alternative.

ΔABC and ΔDEF are equilateral triangles, A(ΔABC) : A(ΔDEF) = 1 : 2. If AB = 4 then what is length of DE?


Solution: We know that, all the angles of an equilateral triangles are equal, i.e., 60°.


⇒ Δ ABC~Δ DEF ……(By AAA Similarity Test)


⇒


And, (Given)


⇒


⇒ DE2 = 2× 42 (∵ AB = 4)


⇒ DE = √32


⇒ DE = 4√2


(A) doesn’t match the solution.


(B) doesn’t match the solution.


(C) doesn’t match the solution.

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