Triangle calculator SSS - result

Please enter the triangle sides:

Obtuse scalene triangle.

Sides: a = 17   b = 18   c = 28

Area: T = 146.9066220086
Perimeter: p = 63
Semiperimeter: s = 31.5

Angle ∠ A = α = 35.65990876961° = 35°39'33″ = 0.62223684886 rad
Angle ∠ B = β = 38.11658121692° = 38°6'57″ = 0.66552464194 rad
Angle ∠ C = γ = 106.2255100135° = 106°13'30″ = 1.85439777456 rad

Height: ha = 17.2833084716
Height: hb = 16.32329133429
Height: hc = 10.49333014347

Median: ma = 21.94988040676
Median: mb = 21.34224459704
Median: mc = 10.51218980208

Inradius: r = 4.66436895265
Circumradius: R = 14.58107304738

Vertex coordinates: A[28; 0] B[0; 0] C[13.375; 10.49333014347]
Centroid: CG[13.79216666667; 3.49877671449]
Coordinates of the circumscribed circle: U[14; -4.07440276324]
Coordinates of the inscribed circle: I[13.5; 4.66436895265]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 144.3410912304° = 144°20'27″ = 0.62223684886 rad
∠ B' = β' = 141.8844187831° = 141°53'3″ = 0.66552464194 rad
∠ C' = γ' = 73.77548998653° = 73°46'30″ = 1.85439777456 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     