# Triangle calculator

Please enter what you know about the triangle:
You have entered side b, c and angle α.

### Obtuse scalene triangle.

Sides: a = 68.40770692634   b = 53.2   c = 100

Area: T = 1709.815504177
Perimeter: p = 221.6077069263
Semiperimeter: s = 110.8043534632

Angle ∠ A = α = 40° = 0.69881317008 rad
Angle ∠ B = β = 29.99330041258° = 29°59'35″ = 0.52334766746 rad
Angle ∠ C = γ = 110.0076995874° = 110°25″ = 1.92199842782 rad

Height: ha = 49.98994253672
Height: hb = 64.27987609687
Height: hc = 34.19663008353

Median: ma = 72.42440168639
Median: mb = 81.43883420915
Median: mc = 35.42443357398

Inradius: r = 15.43110514322
Circumradius: R = 53.21112537894

Vertex coordinates: A[100; 0] B[0; 0] C[59.24664356261; 34.19663008353]
Centroid: CG[53.08221452087; 11.39987669451]
Coordinates of the circumscribed circle: U[50; -18.20554258352]
Coordinates of the inscribed circle: I[57.60435346317; 15.43110514322]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140° = 0.69881317008 rad
∠ B' = β' = 150.0076995874° = 150°25″ = 0.52334766746 rad
∠ C' = γ' = 69.99330041258° = 69°59'35″ = 1.92199842782 rad

# How did we calculate this triangle?

### 1. Input data entered: side b, c and angle α. ### 2. Calculation of the third side a of the triangle using a Law of Cosines 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. ### 3. The triangle circumference is the sum of the lengths of its three sides ### 4. Semiperimeter of the triangle ### 5. The triangle area using Heron's formula ### 6. Calculate the heights of the triangle from its area. ### 7. Calculation of the inner angles of the triangle using a Law of Cosines    