If the area of the equilateral triangle is cm^{2}, find its height.

Let us assume a be the side of the equilateral triangle

We know that,

Area of an equilateral triangle = sq units

It is given that,

Area of the equilateral triangle = 81 cm^{2}

81 cm^{2} = a^{2}

a^{2} = = 324

a = = 18 cm

Height of an equilateral triangle = a

Since, the value of a is 18 cm

Therefore,

Height = × 18

= 9 cm

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