Triangle calculator VC

Please enter the coordinates of the three vertices

Acute scalene triangle.

Sides: a = 5.38551648071   b = 3.60655512755   c = 5.83109518948

Area: T = 9.5
Perimeter: p = 14.82216679774
Semiperimeter: s = 7.41108339887

Angle ∠ A = α = 64.65438240581° = 64°39'14″ = 1.12884221038 rad
Angle ∠ B = β = 37.23548339816° = 37°14'5″ = 0.65498704494 rad
Angle ∠ C = γ = 78.11113419604° = 78°6'41″ = 1.36333001004 rad

Height: ha = 3.52882114254
Height: hb = 5.27696518641
Height: hc = 3.25884731177

Median: ma = 4.03111288741
Median: mb = 5.31550729064
Median: mc = 3.53655339059

Vertex coordinates: A[-1; 2] B[2; 7] C[-3; 5]
Centroid: CG[-0.66766666667; 4.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[1.68767197429; 1.28219070046]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 115.3466175942° = 115°20'46″ = 1.12884221038 rad
∠ B' = β' = 142.7655166018° = 142°45'55″ = 0.65498704494 rad
∠ C' = γ' = 101.889865804° = 101°53'19″ = 1.36333001004 rad

How did we calculate this triangle?

1. We compute side a from coordinates using the Pythagorean theorem 2. We compute side b from coordinates using the Pythagorean theorem 3. We compute side c from coordinates using the Pythagorean theorem 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. 4. The triangle circumference is the sum of the lengths of its three sides 5. Semiperimeter of the triangle 6. The triangle area using Heron's formula 7. Calculate the heights of the triangle from its area. 8. Calculation of the inner angles of the triangle using a Law of Cosines    