# Triangle calculator VC

Please enter the coordinates of the three vertices

### Obtuse scalene triangle.

Sides: a = 3.16222776602   b = 13.60114705087   c = 12.04215945788

Area: T = 17.5
Perimeter: p = 28.80553427477
Semiperimeter: s = 14.40326713738

Angle ∠ A = α = 12.33990872783° = 12°20'21″ = 0.21553576997 rad
Angle ∠ B = β = 113.1998590514° = 113°11'55″ = 1.97656881131 rad
Angle ∠ C = γ = 54.4622322208° = 54°27'44″ = 0.95105468408 rad

Height: ha = 11.06879718106
Height: hb = 2.57332511773
Height: hc = 2.90765917949

Median: ma = 12.7487548784
Median: mb = 5.59901699437
Median: mc = 7.82662379212

Inradius: r = 1.21550523709
Circumradius: R = 7.39989795215

Vertex coordinates: A[-5; 7] B[-4; -5] C[-1; -6]
Centroid: CG[-3.33333333333; -1.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[-0.52107367304; 1.21550523709]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 167.6610912722° = 167°39'39″ = 0.21553576997 rad
∠ B' = β' = 66.80114094864° = 66°48'5″ = 1.97656881131 rad
∠ C' = γ' = 125.5387677792° = 125°32'16″ = 0.95105468408 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    