Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 9.05553851381   b = 10.19880390272   c = 1.41442135624

Area: T = 4
Perimeter: p = 20.66876377277
Semiperimeter: s = 10.33438188638

Angle ∠ A = α = 33.6990067526° = 33°41'24″ = 0.58880026035 rad
Angle ∠ B = β = 141.3440191746° = 141°20'25″ = 2.46768517114 rad
Angle ∠ C = γ = 4.97697407281° = 4°58'11″ = 0.08767383387 rad

Height: ha = 0.88334522086
Height: hb = 0.78444645406
Height: hc = 5.65768542495

Median: ma = 5.70108771255
Median: mb = 4
Median: mc = 9.61876920308

Inradius: r = 0.38770785866
Circumradius: R = 8.16224138587

Vertex coordinates: A[-1; 6] B[0; 5] C[1; -4]
Centroid: CG[0; 2.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-0.48438482333; 0.38770785866]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 146.3109932474° = 146°18'36″ = 0.58880026035 rad
∠ B' = β' = 38.66598082541° = 38°39'35″ = 2.46768517114 rad
∠ C' = γ' = 175.0330259272° = 175°1'49″ = 0.08767383387 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     