17 17 20 triangle

Acute isosceles triangle.

Sides: a = 17   b = 17   c = 20

Area: T = 137.4777270849
Perimeter: p = 54
Semiperimeter: s = 27

Angle ∠ A = α = 53.96881209275° = 53°58'5″ = 0.94219214013 rad
Angle ∠ B = β = 53.96881209275° = 53°58'5″ = 0.94219214013 rad
Angle ∠ C = γ = 72.06437581449° = 72°3'50″ = 1.2587749851 rad

Height: ha = 16.17437965704
Height: hb = 16.17437965704
Height: hc = 13.74877270849

Median: ma = 16.5
Median: mb = 16.5
Median: mc = 13.74877270849

Vertex coordinates: A[20; 0] B[0; 0] C[10; 13.74877270849]
Centroid: CG[10; 4.5832575695]
Coordinates of the circumscribed circle: U[10; 3.23768987052]
Coordinates of the inscribed circle: I[10; 5.09217507722]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 126.0321879072° = 126°1'55″ = 0.94219214013 rad
∠ B' = β' = 126.0321879072° = 126°1'55″ = 0.94219214013 rad
∠ C' = γ' = 107.9366241855° = 107°56'10″ = 1.2587749851 rad

How did we calculate this triangle?

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. 1. The triangle circumference is the sum of the lengths of its three sides 2. Semiperimeter of the triangle 3. The triangle area using Heron's formula 4. Calculate the heights of the triangle from its area. 5. Calculation of the inner angles of the triangle using a Law of Cosines    