Triangle calculator VC

Please enter the coordinates of the three vertices

Acute scalene triangle.

Sides: a = 7.61657731059   b = 8.54440037453   c = 6.08327625303

Area: T = 22.5
Perimeter: p = 22.24325393815
Semiperimeter: s = 11.12112696907

Angle ∠ A = α = 59.98216325724° = 59°58'54″ = 1.04768769791 rad
Angle ∠ B = β = 76.26437316944° = 76°15'49″ = 1.33110532179 rad
Angle ∠ C = γ = 43.75546357332° = 43°45'17″ = 0.76436624566 rad

Height: ha = 5.90987894787
Height: hb = 5.26768516238
Height: hc = 7.39879544287

Median: ma = 6.36439610307
Median: mb = 5.40883269132
Median: mc = 7.5

Inradius: r = 2.023315029
Circumradius: R = 4.39877828308

Vertex coordinates: A[0; 0] B[6; 1] C[3; 8]
Centroid: CG[3; 3]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[0.49545478487; 2.023315029]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 120.0188367428° = 120°1'6″ = 1.04768769791 rad
∠ B' = β' = 103.7366268306° = 103°44'11″ = 1.33110532179 rad
∠ C' = γ' = 136.2455364267° = 136°14'43″ = 0.76436624566 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     