Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 6.08327625303   b = 5.09990195136   c = 2.23660679775

Area: T = 5.5
Perimeter: p = 13.41878500214
Semiperimeter: s = 6.70989250107

Angle ∠ A = α = 105.2555118703° = 105°15'18″ = 1.83770483759 rad
Angle ∠ B = β = 53.97326266149° = 53°58'21″ = 0.94220000404 rad
Angle ∠ C = γ = 20.7722254682° = 20°46'20″ = 0.36325442373 rad

Height: ha = 1.80883888604
Height: hb = 2.15772774865
Height: hc = 4.91993495505

Median: ma = 2.5
Median: mb = 3.80878865529
Median: mc = 5.5

Inradius: r = 0.82198034694
Circumradius: R = 3.1522461979

Vertex coordinates: A[0; -4] B[-1; -2] C[5; -3]
Centroid: CG[1.33333333333; -3]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[0.5966220705; 0.82198034694]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 74.74548812969° = 74°44'42″ = 1.83770483759 rad
∠ B' = β' = 126.0277373385° = 126°1'39″ = 0.94220000404 rad
∠ C' = γ' = 159.2287745318° = 159°13'40″ = 0.36325442373 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     