# 8 17 19 triangle

### Obtuse scalene triangle.

Sides: a = 8   b = 17   c = 19

Area: T = 67.97105818719
Perimeter: p = 44
Semiperimeter: s = 22

Angle ∠ A = α = 24.89895564788° = 24°53'22″ = 0.43444047099 rad
Angle ∠ B = β = 63.4255030481° = 63°25'30″ = 1.10769756101 rad
Angle ∠ C = γ = 91.68554130402° = 91°41'7″ = 1.66002123336 rad

Height: ha = 16.9932645468
Height: hb = 7.99765390437
Height: hc = 7.15547980918

Median: ma = 17.57883958312
Median: mb = 11.84327192823
Median: mc = 9.28770878105

Inradius: r = 3.09895719033
Circumradius: R = 9.50441116643

Vertex coordinates: A[19; 0] B[0; 0] C[3.57989473684; 7.15547980918]
Centroid: CG[7.52663157895; 2.38549326973]
Coordinates of the circumscribed circle: U[9.5; -0.2879532696]
Coordinates of the inscribed circle: I[5; 3.09895719033]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 155.1110443521° = 155°6'38″ = 0.43444047099 rad
∠ B' = β' = 116.5754969519° = 116°34'30″ = 1.10769756101 rad
∠ C' = γ' = 88.31545869598° = 88°18'53″ = 1.66002123336 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    