Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 4.12331056256   b = 2.23660679775   c = 5.83109518948

Area: T = 3.5
Perimeter: p = 12.1990125498
Semiperimeter: s = 6.0955062749

Angle ∠ A = α = 32.47111922908° = 32°28'16″ = 0.56767292175 rad
Angle ∠ B = β = 16.92875130641° = 16°55'39″ = 0.29554408371 rad
Angle ∠ C = γ = 130.6011294645° = 130°36'5″ = 2.27994225989 rad

Height: ha = 1.69877493753
Height: hb = 3.13304951685
Height: hc = 1.2200490096

Median: ma = 3.9055124838
Median: mb = 4.92444289009
Median: mc = 1.58111388301

Inradius: r = 0.57442352695
Circumradius: R = 3.84399085873

Vertex coordinates: A[-5; 10] B[0; 7] C[-4; 8]
Centroid: CG[-3; 8.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[1.88767730282; 0.57442352695]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 147.5298807709° = 147°31'44″ = 0.56767292175 rad
∠ B' = β' = 163.0722486936° = 163°4'21″ = 0.29554408371 rad
∠ C' = γ' = 49.3998705355° = 49°23'55″ = 2.27994225989 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     