Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 8.24662112512   b = 15.62204993518   c = 12.64991106407

Area: T = 52
Perimeter: p = 36.51658212437
Semiperimeter: s = 18.25879106219

Angle ∠ A = α = 31.75994800848° = 31°45'34″ = 0.55443074962 rad
Angle ∠ B = β = 94.3998705355° = 94°23'55″ = 1.64875682181 rad
Angle ∠ C = γ = 53.84218145602° = 53°50'31″ = 0.94397169393 rad

Height: ha = 12.61218525019
Height: hb = 6.65879177565
Height: hc = 8.22219219164

Median: ma = 13.60114705087
Median: mb = 7.28801098893
Median: mc = 10.77703296143

Inradius: r = 2.84880805431
Circumradius: R = 7.83333228419

Vertex coordinates: A[-5; -6] B[7; -2] C[5; 6]
Centroid: CG[2.33333333333; -0.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-0.21990831187; 2.84880805431]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 148.2410519915° = 148°14'26″ = 0.55443074962 rad
∠ B' = β' = 85.6011294645° = 85°36'5″ = 1.64875682181 rad
∠ C' = γ' = 126.158818544° = 126°9'29″ = 0.94397169393 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     