Answer:
Sides: a = 12 b = 12 c = 6
Area: T = 34.857
Perimeter: p = 30
Semiperimeter: s = 15
Angle ∠ A = α = 75.522° = 75°31'21″ = 1.318 rad
Angle ∠ B = β = 75.522° = 75°31'21″ = 1.318 rad
Angle ∠ C = γ = 28.955° = 28°57'18″ = 0.505 rad
Height: ha = 5.809
Height: hb = 5.809
Height: hc = 11.619
Median: ma = 7.348
Median: mb = 7.348
Median: mc = 11.619
Inradius: r = 2.324
Circumradius: R = 6.197
Vertex coordinates: A[6; 0] B[0; 0] C[3; 11.619]
Centroid: CG[3; 3.873]
Coordinates of the circumscribed circle: U[3; 5.422]
Coordinates of the inscribed circle: I[3; 2.324]
Exterior (or external, outer) angles of the triangle:
∠ A' = α' = 104.478° = 104°28'39″ = 1.318 rad
∠ B' = β' = 104.478° = 104°28'39″ = 1.318 rad
∠ C' = γ' = 151.045° = 151°2'42″ = 0.505 rad
