Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 14.14221356237   b = 9.84988578018   c = 5.38551648071

Area: T = 19
Perimeter: p = 29.37661582327
Semiperimeter: s = 14.68880791163

Angle ∠ A = α = 134.2366101539° = 134°14'10″ = 2.34328619469 rad
Angle ∠ B = β = 29.93215118405° = 29°55'53″ = 0.52224034317 rad
Angle ∠ C = γ = 15.83223866204° = 15°49'57″ = 0.2766327275 rad

Height: ha = 2.68770057685
Height: hb = 3.85883154275
Height: hc = 7.05664228507

Median: ma = 3.60655512755
Median: mb = 9.5
Median: mc = 11.8854864324

Inradius: r = 1.2943566017
Circumradius: R = 9.86992982066

Vertex coordinates: A[1; -6] B[6; -4] C[-8; -2]
Centroid: CG[-0.33333333333; -4]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[2.24767199243; 1.2943566017]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 45.76438984609° = 45°45'50″ = 2.34328619469 rad
∠ B' = β' = 150.0688488159° = 150°4'7″ = 0.52224034317 rad
∠ C' = γ' = 164.168761338° = 164°10'3″ = 0.2766327275 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     