13 17 25 triangle

Obtuse scalene triangle.

Sides: a = 13   b = 17   c = 25

Area: T = 102.3099273773
Perimeter: p = 55
Semiperimeter: s = 27.5

Angle ∠ A = α = 28.78105000852° = 28°46'50″ = 0.50223144869 rad
Angle ∠ B = β = 39.02202878409° = 39°1'13″ = 0.68110324979 rad
Angle ∠ C = γ = 112.1999212074° = 112°11'57″ = 1.95882456688 rad

Height: ha = 15.74398882728
Height: hb = 12.03663851498
Height: hc = 8.18547419019

Median: ma = 20.36554118544
Median: mb = 18.02108212909
Median: mc = 8.52993610546

Vertex coordinates: A[25; 0] B[0; 0] C[10.1; 8.18547419019]
Centroid: CG[11.7; 2.72882473006]
Coordinates of the circumscribed circle: U[12.5; -5.10109549844]
Coordinates of the inscribed circle: I[10.5; 3.72203372281]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 151.2199499915° = 151°13'10″ = 0.50223144869 rad
∠ B' = β' = 140.9879712159° = 140°58'47″ = 0.68110324979 rad
∠ C' = γ' = 67.80107879261° = 67°48'3″ = 1.95882456688 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    