# 5 17 19 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 17   c = 19

Area: T = 40.84334511274
Perimeter: p = 41
Semiperimeter: s = 20.5

Angle ∠ A = α = 14.6499222929° = 14°38'57″ = 0.2565677173 rad
Angle ∠ B = β = 59.30111062669° = 59°18'4″ = 1.03549995544 rad
Angle ∠ C = γ = 106.0549670804° = 106°2'59″ = 1.85109159262 rad

Height: ha = 16.3377380451
Height: hb = 4.80551118973
Height: hc = 4.2999310645

Median: ma = 17.85435710714
Median: mb = 10.98986304879
Median: mc = 8.17700673192

Inradius: r = 1.99223634696
Circumradius: R = 9.88553056942

Vertex coordinates: A[19; 0] B[0; 0] C[2.55326315789; 4.2999310645]
Centroid: CG[7.18442105263; 1.43331035483]
Coordinates of the circumscribed circle: U[9.5; -2.73329962802]
Coordinates of the inscribed circle: I[3.5; 1.99223634696]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 165.3510777071° = 165°21'3″ = 0.2565677173 rad
∠ B' = β' = 120.6998893733° = 120°41'56″ = 1.03549995544 rad
∠ C' = γ' = 73.95503291958° = 73°57'1″ = 1.85109159262 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    