Question

find the area of a equilateral triangle of each side 2a units

Answer 1

mark angles as angle1.2.3.
equilateral have all angles of 60 so
angle 1plus angle2 plus angle 3 =180
60+60+60=180
180=180
180-180
0

Answer 2

Area of equilateral triangle= √3/4 s^2.
s=2a. ( Given).
So area= √3/4 2a^2
= 0.433× 2a^2
=0.866a^2
Hope it helps.