20.8 15.7 12.4 triangle

Obtuse scalene triangle.

Sides: a = 20.8   b = 15.7   c = 12.4

Area: T = 97.00326086956
Perimeter: p = 48.9
Semiperimeter: s = 24.45

Angle ∠ A = α = 94.77218240809° = 94°46'19″ = 1.65440803683 rad
Angle ∠ B = β = 48.78105658324° = 48°46'50″ = 0.85113814848 rad
Angle ∠ C = γ = 36.44876100867° = 36°26'51″ = 0.63661308005 rad

Height: ha = 9.3277173913
Height: hb = 12.3577020216
Height: hc = 15.64655820477

Median: ma = 9.59898383719
Median: mb = 15.21876706496
Median: mc = 17.35329536391

Inradius: r = 3.96773868587
Circumradius: R = 10.43661729402

Vertex coordinates: A[12.4; 0] B[0; 0] C[13.70660483871; 15.64655820477]
Centroid: CG[8.7022016129; 5.21551940159]
Coordinates of the circumscribed circle: U[6.2; 8.39548618594]
Coordinates of the inscribed circle: I[8.75; 3.96773868587]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 85.22881759191° = 85°13'41″ = 1.65440803683 rad
∠ B' = β' = 131.2199434168° = 131°13'10″ = 0.85113814848 rad
∠ C' = γ' = 143.5522389913° = 143°33'9″ = 0.63661308005 rad

How did we calculate this triangle?

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     