Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 2.23660679775   b = 5.83109518948   c = 3.60655512755

Area: T = 0.5
Perimeter: p = 11.67325711478
Semiperimeter: s = 5.83662855739

Angle ∠ A = α = 2.72663109939° = 2°43'35″ = 0.04875831033 rad
Angle ∠ B = β = 172.8754983651° = 172°52'30″ = 3.0177237659 rad
Angle ∠ C = γ = 4.3998705355° = 4°23'55″ = 0.07767718913 rad

Height: ha = 0.44772135955
Height: hb = 0.17114985851
Height: hc = 0.27773500981

Median: ma = 4.7176990566
Median: mb = 0.70771067812
Median: mc = 4.03111288741

Inradius: r = 0.08656709278
Circumradius: R = 23.50553185471

Vertex coordinates: A[-1; 3] B[2; 1] C[4; 0]
Centroid: CG[1.66766666667; 1.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-0.68553674224; 0.08656709278]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 177.2743689006° = 177°16'25″ = 0.04875831033 rad
∠ B' = β' = 7.12550163489° = 7°7'30″ = 3.0177237659 rad
∠ C' = γ' = 175.6011294645° = 175°36'5″ = 0.07767718913 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     