Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 10.63301458127   b = 4.4722135955   c = 6.40331242374

Area: T = 6
Perimeter: p = 21.50554060052
Semiperimeter: s = 10.75327030026

Angle ∠ A = α = 155.2254859431° = 155°13'29″ = 2.7099184878 rad
Angle ∠ B = β = 10.15442665802° = 10°9'15″ = 0.17772253849 rad
Angle ∠ C = γ = 14.62108739886° = 14°37'15″ = 0.25551823906 rad

Height: ha = 1.12988650421
Height: hb = 2.6833281573
Height: hc = 1.87440851427

Median: ma = 1.5
Median: mb = 8.48552813742
Median: mc = 7.5

Vertex coordinates: A[0; 0] B[-4; 5] C[4; -2]
Centroid: CG[0; 1]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[3.1155495703; 0.55879992304]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 24.77551405688° = 24°46'31″ = 2.7099184878 rad
∠ B' = β' = 169.846573342° = 169°50'45″ = 0.17772253849 rad
∠ C' = γ' = 165.3799126011° = 165°22'45″ = 0.25551823906 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    