# 6 17 19 triangle

### Obtuse scalene triangle.

Sides: a = 6   b = 17   c = 19

Area: T = 50.2199601592
Perimeter: p = 42
Semiperimeter: s = 21

Angle ∠ A = α = 18.10994650096° = 18°6'34″ = 0.31660697902 rad
Angle ∠ B = β = 61.72662863686° = 61°43'35″ = 1.07773269322 rad
Angle ∠ C = γ = 100.1644248622° = 100°9'51″ = 1.74881959312 rad

Height: ha = 16.73332005307
Height: hb = 5.90658354814
Height: hc = 5.28441685886

Median: ma = 17.77663888346
Median: mb = 11.23661025271
Median: mc = 8.5

Inradius: r = 2.39904572187
Circumradius: R = 9.65114710204

Vertex coordinates: A[19; 0] B[0; 0] C[2.84221052632; 5.28441685886]
Centroid: CG[7.28107017544; 1.76113895295]
Coordinates of the circumscribed circle: U[9.5; -1.70332007683]
Coordinates of the inscribed circle: I[4; 2.39904572187]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 161.891053499° = 161°53'26″ = 0.31660697902 rad
∠ B' = β' = 118.2743713631° = 118°16'25″ = 1.07773269322 rad
∠ C' = γ' = 79.83657513783° = 79°50'9″ = 1.74881959312 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    