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प्रश्न
Find the area of an equilateral triangle whose perimeter is 180 cm
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उत्तर
Perimeter of an equilateral triangle = 180 cm
3a = 180
a = `180/3`
= 60 m
Area of an equilateral triangle
= `sqrt(3)/4 "a"^2 "sq.unit"`
= `sqrt(3)/4 xx 60 xx 60 "sq.m"`
= `sqrt(3) xx 15 xx 60 "sq.m"`
= 1.732 × 15 × 60 sq.m
= 1558.8 sq.m
Area of an equilateral triangle = 1558.8 sq.m
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