In equilateral triangle,
- All sides are equal
- All angles all equal 60°
In equilateral ∆ ABC,
- AB = AC = BC
- ∠A = ∠B = ∠C = 60°
But, why are all angles 60°?
In equilateral triangle, all angles are equal.
Let ∠A = ∠B = ∠C = x
In ∆ABC
Sum of angles is 180°
∠A + ∠B + ∠C = 180°
x + x + x = 180°
3x = 180°
x = (180°)/3
x = 60°
So, ∠A = ∠B = ∠C = 60 °
Thus, all angles are 60°
For equilateral triangle
Perimeter = 3a
Check proof
Area = √3/4 a 2
Check proof