Triangle calculator

Please enter what you know about the triangle:
You have entered side a, b and c (as equilateral triangle).

Equilateral triangle.

Sides: a = 100   b = 100   c = 100

Area: T = 4330.127701892
Perimeter: p = 300
Semiperimeter: s = 150

Angle ∠ A = α = 60° = 1.04771975512 rad
Angle ∠ B = β = 60° = 1.04771975512 rad
Angle ∠ C = γ = 60° = 1.04771975512 rad

Height: ha = 86.60325403784
Height: hb = 86.60325403784
Height: hc = 86.60325403784

Median: ma = 86.60325403784
Median: mb = 86.60325403784
Median: mc = 86.60325403784

Inradius: r = 28.86875134595
Circumradius: R = 57.7355026919

Vertex coordinates: A[100; 0] B[0; 0] C[50; 86.60325403784]
Centroid: CG[50; 28.86875134595]
Coordinates of the circumscribed circle: U[50; 28.86875134595]
Coordinates of the inscribed circle: I[50; 28.86875134595]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 120° = 1.04771975512 rad
∠ B' = β' = 120° = 1.04771975512 rad
∠ C' = γ' = 120° = 1.04771975512 rad

How did we calculate this triangle?

1. Input data entered: side a, b and c (as equilateral triangle). 2. The triangle circumference is the sum of the lengths of its three sides 3. Semiperimeter of the triangle 4. The triangle area using Heron's formula 5. Calculate the heights of the triangle from its area. 6. Calculation of the inner angles of the triangle using a Law of Cosines     