Triangle calculator

Please enter what you know about the triangle:
You have entered side a, b and c.

Obtuse scalene triangle.

Sides: a = 105   b = 780   c = 772

Area: T = 40528.50881139
Perimeter: p = 1657
Semiperimeter: s = 828.5

Angle ∠ A = α = 7.7366093525° = 7°44'10″ = 0.13550203033 rad
Angle ∠ B = β = 90.49216074957° = 90°29'30″ = 1.57993764962 rad
Angle ∠ C = γ = 81.77222989793° = 81°46'20″ = 1.42771958541 rad

Height: ha = 771.9721583122
Height: hb = 103.9199251574
Height: hc = 104.996613501

Median: ma = 774.2322361762
Median: mb = 389.1077311676
Median: mc = 400.8954624559

Inradius: r = 48.91879337524
Circumradius: R = 390.0144356205

Vertex coordinates: A[772; 0] B[0; 0] C[-0.90109067358; 104.996613501]
Centroid: CG[257.0333031088; 34.999871167]
Coordinates of the circumscribed circle: U[386; 55.81439592418]
Coordinates of the inscribed circle: I[48.5; 48.91879337524]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 172.2643906475° = 172°15'50″ = 0.13550203033 rad
∠ B' = β' = 89.50883925043° = 89°30'30″ = 1.57993764962 rad
∠ C' = γ' = 98.22877010207° = 98°13'40″ = 1.42771958541 rad

How did we calculate this triangle?

1. Input data entered: side a, b and c. 2. The triangle circumference is the sum of the lengths of its three sides 3. Semiperimeter of the triangle 4. The triangle area using Heron's formula 5. Calculate the heights of the triangle from its area. 6. Calculation of the inner angles of the triangle using a Law of Cosines     