# 19 24 26 triangle

### Acute scalene triangle.

Sides: a = 19   b = 24   c = 26

Area: T = 218.4643812793
Perimeter: p = 69
Semiperimeter: s = 34.5

Angle ∠ A = α = 44.44334156294° = 44°26'36″ = 0.77656839336 rad
Angle ∠ B = β = 62.18662319147° = 62°11'10″ = 1.08553544963 rad
Angle ∠ C = γ = 73.37703524559° = 73°22'13″ = 1.28105542237 rad

Height: ha = 22.99661908203
Height: hb = 18.20553177327
Height: hc = 16.80549086764

Median: ma = 23.14662739982
Median: mb = 19.35220024804
Median: mc = 17.30660682999

Inradius: r = 6.33222844288
Circumradius: R = 13.56774643874

Vertex coordinates: A[26; 0] B[0; 0] C[8.86553846154; 16.80549086764]
Centroid: CG[11.62217948718; 5.60216362255]
Coordinates of the circumscribed circle: U[13; 3.88327940845]
Coordinates of the inscribed circle: I[10.5; 6.33222844288]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 135.5576584371° = 135°33'24″ = 0.77656839336 rad
∠ B' = β' = 117.8143768085° = 117°48'50″ = 1.08553544963 rad
∠ C' = γ' = 106.6329647544° = 106°37'47″ = 1.28105542237 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    