The smaller diagonal of a rhombus is equal to the length of its sides. If the length of each side is 4 cm, then what is the area (in cm2) of an equilateral triangle with side equal to the bigger diagonal of the rhombus?
The smaller diagonal of a rhombus is equal to the length of its sides. If the length of each side is 4 cm, then what is the area (in cm2) of an equilateral triangle with side equal to the bigger diagonal of the rhombus? Correct Answer 12√3
Let ABCD be the given rhombus and AC be the bigger diagonal.
So, AB = BD = 4 cm
So, ΔABD is an equilateral triangle
⇒ Ar (ΔABD) = √3 (side)2/4
⇒ Ar (ΔABD) = 4√3
Now, Ar (rhombus ABCD) = 2
⇒ Ar (rhombus ABCD) = 8√3
Also, Ar (rhombus ABCD) = ( 1/2) × AC ×BD
⇒ (1/2) × AC × BD = 8√3
⇒ AC = (8√3 × 2)/4 = 4√3
Now, AC is the side of new equilateral Δ
⇒ Area of new triangle = /4
⇒ Required area = 12√3 cm2
∴ the correct option is 4)
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Feb 20, 2025