Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 21.93217121995   b = 68.73986354243   c = 75.60442326857

Area: T = 742.9176549822
Perimeter: p = 166.275458031
Semiperimeter: s = 83.13772901548

Angle ∠ A = α = 16.61330020417° = 16°36'47″ = 0.29899515843 rad
Angle ∠ B = β = 63.64987152482° = 63°38'55″ = 1.11108796457 rad
Angle ∠ C = γ = 99.738828271° = 99°44'18″ = 1.74107614236 rad

Height: ha = 67.74881578334
Height: hb = 21.61656909498
Height: hc = 19.65327766616

Median: ma = 71.41660346141
Median: mb = 43.78664134179
Median: mc = 34.2643683398

Inradius: r = 8.93660207488
Circumradius: R = 38.35547830179

Vertex coordinates: A[0; 30; 0] B[60; 76; 0] C[60; 60; 15]
Centroid: CG[40; 55.33333333333; 5]
Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 163.3876997958° = 163°23'13″ = 0.29899515843 rad
∠ B' = β' = 116.3511284752° = 116°21'5″ = 1.11108796457 rad
∠ C' = γ' = 80.262171729° = 80°15'42″ = 1.74107614236 rad

How did we calculate this triangle?

1. We compute side a from coordinates using the Pythagorean theorem 2. We compute side b from coordinates using the Pythagorean theorem 3. We compute side c from coordinates using the Pythagorean theorem 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. 4. The triangle circumference is the sum of the lengths of its three sides 5. Semiperimeter of the triangle 6. The triangle area using Heron's formula 7. Calculate the heights of the triangle from its area. 8. Calculation of the inner angles of the triangle using a Law of Cosines     