Triangle calculator SSS - result

Please enter the triangle sides:

Acute scalene triangle.

Sides: a = 15   b = 21   c = 23

Area: T = 153.7310893122
Perimeter: p = 59
Semiperimeter: s = 29.5

Angle ∠ A = α = 39.53662915601° = 39°32'11″ = 0.69900384618 rad
Angle ∠ B = β = 63.0243617313° = 63°1'25″ = 1.10999696286 rad
Angle ∠ C = γ = 77.44400911269° = 77°26'24″ = 1.35215845632 rad

Height: ha = 20.49774524162
Height: hb = 14.64110374402
Height: hc = 13.36879037497

Median: ma = 20.70662792408
Median: mb = 16.33224829711
Median: mc = 14.16986273153

Inradius: r = 5.2111216716
Circumradius: R = 11.78219519761

Vertex coordinates: A[23; 0] B[0; 0] C[6.80443478261; 13.36879037497]
Centroid: CG[9.93547826087; 4.45659679166]
Coordinates of the circumscribed circle: U[11.5; 2.5622107017]
Coordinates of the inscribed circle: I[8.5; 5.2111216716]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140.464370844° = 140°27'49″ = 0.69900384618 rad
∠ B' = β' = 116.9766382687° = 116°58'35″ = 1.10999696286 rad
∠ C' = γ' = 102.5659908873° = 102°33'36″ = 1.35215845632 rad

How did we calculate this triangle?

1. The triangle circumference is the sum of the lengths of its three sides 2. Semiperimeter of the triangle 3. The triangle area using Heron's formula 4. Calculate the heights of the triangle from its area. 5. Calculation of the inner angles of the triangle using a Law of Cosines     