Triangle calculator

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

Obtuse scalene triangle.

Sides: a = 12.07989388927   b = 11.5   c = 0.8

Area: T = 3.25326911935
Perimeter: p = 24.37989388927
Semiperimeter: s = 12.18994694464

Angle ∠ A = α = 135° = 2.35661944902 rad
Angle ∠ B = β = 42.31657205937° = 42°18'57″ = 0.73985486497 rad
Angle ∠ C = γ = 2.68442794063° = 2°41'3″ = 0.04768495137 rad

Height: ha = 0.53985723402
Height: hb = 0.56656854249
Height: hc = 8.13217279836

Median: ma = 5.4744468815
Median: mb = 6.34109685685
Median: mc = 11.78662369901

Inradius: r = 0.26768443617
Circumradius: R = 8.54110996006

Vertex coordinates: A[0.8; 0] B[0; 0] C[8.93217279836; 8.13217279836]
Centroid: CG[3.24439093279; 2.71105759945]
Coordinates of the circumscribed circle: U[0.4; 8.53217279836]
Coordinates of the inscribed circle: I[0.68994694464; 0.26768443617]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 45° = 2.35661944902 rad
∠ B' = β' = 137.6844279406° = 137°41'3″ = 0.73985486497 rad
∠ C' = γ' = 177.3165720594° = 177°18'57″ = 0.04768495137 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     