# Triangle calculator

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

### Obtuse scalene triangle.

Sides: a = 350.1911487603   b = 408   c = 90

Area: T = 12982.48105026
Perimeter: p = 848.1911487603
Semiperimeter: s = 424.0965743802

Angle ∠ A = α = 45° = 0.78553981634 rad
Angle ∠ B = β = 124.5329570942° = 124°31'46″ = 2.1733451029 rad
Angle ∠ C = γ = 10.47704290582° = 10°28'14″ = 0.18327434612 rad

Height: ha = 74.14550375704
Height: hb = 63.64396103068
Height: hc = 288.5499566724

Median: ma = 237.9576887907
Median: mb = 154.1143720982
Median: mc = 377.5243560847

Inradius: r = 30.61221452345
Circumradius: R = 247.6232775598

Vertex coordinates: A[90; 0] B[0; 0] C[-198.5499566724; 288.5499566724]
Centroid: CG[-36.16765222414; 96.16765222414]
Coordinates of the circumscribed circle: U[45; 243.5499566724]
Coordinates of the inscribed circle: I[16.09657438015; 30.61221452345]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 135° = 0.78553981634 rad
∠ B' = β' = 55.47704290582° = 55°28'14″ = 2.1733451029 rad
∠ C' = γ' = 169.5329570942° = 169°31'46″ = 0.18327434612 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    