# 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    