# 11 19 26 triangle

### Obtuse scalene triangle.

Sides: a = 11   b = 19   c = 26

Area: T = 92.56334917232
Perimeter: p = 56
Semiperimeter: s = 28

Angle ∠ A = α = 22.0098922636° = 22°32″ = 0.38441281648 rad
Angle ∠ B = β = 40.33881268008° = 40°20'17″ = 0.70440331268 rad
Angle ∠ C = γ = 117.6532950563° = 117°39'11″ = 2.0533431362 rad

Height: ha = 16.83297257679
Height: hb = 9.74435254446
Height: hc = 7.12202685941

Median: ma = 22.0966379794
Median: mb = 17.55770498661
Median: mc = 8.48552813742

Inradius: r = 3.30658389901
Circumradius: R = 14.67664126408

Vertex coordinates: A[26; 0] B[0; 0] C[8.38546153846; 7.12202685941]
Centroid: CG[11.46215384615; 2.37334228647]
Coordinates of the circumscribed circle: U[13; -6.8121540795]
Coordinates of the inscribed circle: I[9; 3.30658389901]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 157.9911077364° = 157°59'28″ = 0.38441281648 rad
∠ B' = β' = 139.6621873199° = 139°39'43″ = 0.70440331268 rad
∠ C' = γ' = 62.34770494369° = 62°20'49″ = 2.0533431362 rad

# How did we calculate this triangle?

Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS. ### 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    