Question

find the area of equalateral triangle whose one side is 1km

Answer 1

1 km=1000m =a ,where a is side of equilateral triangle
now, area of equilateral tri =
$\sqrt{3 } {a}^{2} \div 4$
from this ,
$\sqrt{3} \times 1000 \times 1000 \div 4$
$\sqrt{3} \times 250000$
=433012.70