Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 8.944427191   b = 15.23215462117   c = 11.66219037897

Area: T = 52
Perimeter: p = 35.83877219114
Semiperimeter: s = 17.91988609557

Angle ∠ A = α = 35.83876529543° = 35°50'16″ = 0.62554850402 rad
Angle ∠ B = β = 94.3998705355° = 94°23'55″ = 1.64875682181 rad
Angle ∠ C = γ = 49.76436416907° = 49°45'49″ = 0.86985393953 rad

Height: ha = 11.6287553483
Height: hb = 6.82879345087
Height: hc = 8.91879264274

Median: ma = 12.80662484749
Median: mb = 7.07110678119
Median: mc = 11.04553610172

Inradius: r = 2.90219701715
Circumradius: R = 7.6388271746

Vertex coordinates: A[5; 10] B[-1; 0] C[-9; 4]
Centroid: CG[-1.66766666667; 4.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-0.22332284747; 2.90219701715]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 144.1622347046° = 144°9'44″ = 0.62554850402 rad
∠ B' = β' = 85.6011294645° = 85°36'5″ = 1.64875682181 rad
∠ C' = γ' = 130.2366358309° = 130°14'11″ = 0.86985393953 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     