Triangle calculator SSS - result

Please enter the triangle sides:

Acute isosceles triangle.

Sides: a = 16   b = 20   c = 20

Area: T = 146.6422422239
Perimeter: p = 56
Semiperimeter: s = 28

Angle ∠ A = α = 47.15663569564° = 47°9'23″ = 0.82330336921 rad
Angle ∠ B = β = 66.42218215218° = 66°25'19″ = 1.15992794807 rad
Angle ∠ C = γ = 66.42218215218° = 66°25'19″ = 1.15992794807 rad

Height: ha = 18.33303027798
Height: hb = 14.66442422239
Height: hc = 14.66442422239

Median: ma = 18.33303027798
Median: mb = 15.10996688705
Median: mc = 15.10996688705

Inradius: r = 5.23772293657
Circumradius: R = 10.91108945118

Vertex coordinates: A[20; 0] B[0; 0] C[6.4; 14.66442422239]
Centroid: CG[8.8; 4.88880807413]
Coordinates of the circumscribed circle: U[10; 4.36443578047]
Coordinates of the inscribed circle: I[8; 5.23772293657]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 132.8443643044° = 132°50'37″ = 0.82330336921 rad
∠ B' = β' = 113.5788178478° = 113°34'41″ = 1.15992794807 rad
∠ C' = γ' = 113.5788178478° = 113°34'41″ = 1.15992794807 rad

How did we calculate this triangle?

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     