Triangle calculator SSS - result

Please enter the triangle sides:

Acute scalene triangle.

Sides: a = 14   b = 20   c = 21

Area: T = 134.533043336
Perimeter: p = 55
Semiperimeter: s = 27.5

Angle ∠ A = α = 39.83881498056° = 39°50'17″ = 0.6955306882 rad
Angle ∠ B = β = 66.23303095773° = 66°13'49″ = 1.15659369667 rad
Angle ∠ C = γ = 73.9321540617° = 73°55'54″ = 1.29903488048 rad

Height: ha = 19.21986333371
Height: hb = 13.4533043336
Height: hc = 12.81224222248

Median: ma = 19.27443352674
Median: mb = 14.78217454991
Median: mc = 13.7022189606

Inradius: r = 4.89220157585
Circumradius: R = 10.92768955974

Vertex coordinates: A[21; 0] B[0; 0] C[5.64328571429; 12.81224222248]
Centroid: CG[8.8810952381; 4.27108074083]
Coordinates of the circumscribed circle: U[10.5; 3.02444086029]
Coordinates of the inscribed circle: I[7.5; 4.89220157585]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140.1621850194° = 140°9'43″ = 0.6955306882 rad
∠ B' = β' = 113.7769690423° = 113°46'11″ = 1.15659369667 rad
∠ C' = γ' = 106.0688459383° = 106°4'6″ = 1.29903488048 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     