Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 5.38551648071   b = 9.84988578018   c = 4.4722135955

Area: T = 1
Perimeter: p = 19.70661585639
Semiperimeter: s = 9.8533079282

Angle ∠ A = α = 2.60325622025° = 2°36'9″ = 0.04554232794 rad
Angle ∠ B = β = 175.2366358309° = 175°14'11″ = 3.05884514217 rad
Angle ∠ C = γ = 2.16110794882° = 2°9'40″ = 0.03877179525 rad

Height: ha = 0.37113906764
Height: hb = 0.2033069233
Height: hc = 0.44772135955

Median: ma = 7.15989105316
Median: mb = 0.5
Median: mc = 7.61657731059

Inradius: r = 0.10114911147
Circumradius: R = 59.29879763567

Vertex coordinates: A[0; -3] B[-2; 1] C[-4; 6]
Centroid: CG[-2; 1.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-1.21878933769; 0.10114911147]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 177.3977437798° = 177°23'51″ = 0.04554232794 rad
∠ B' = β' = 4.76436416907° = 4°45'49″ = 3.05884514217 rad
∠ C' = γ' = 177.8398920512° = 177°50'20″ = 0.03877179525 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     