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प्रश्न
If the area of an equilateral triangle is `81sqrt3 cm^2` find its height.
उत्तर
Area of equilateral triangle=`81sqrt3 cm^2`
Area of equilateral triangle =`(sqrt3/4xxa^2)` where a is the length of the side
⇒ `81sqrt3=sqrt3/4xxa^2`
⇒`324=a^2`
⇒ `a=18 cm`
Height of triangle=`sqrt3/2xxa`
=`sqrt3/2xx18`
=`9sqrt3 cm`
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