In equilateral triangle all sides are equal.
AB = BC = CA
∴ ∠C = ∠A = ∠B = x° (Angles opposite to equal sides are equal).
Sum of angles of triangle = 180°
∠A + ∠B + ∠C = 180°
x° + x° + x° = 180°
3x° = 180°
x = 60°.
Hence, proved that angles of an equilateral triangle are 60° each.
