Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 11.18803398875   b = 5.09990195136   c = 7.81102496759

Area: T = 17.5
Perimeter: p = 24.0989609077
Semiperimeter: s = 12.04548045385

Angle ∠ A = α = 118.4965638618° = 118°29'44″ = 2.06881390431 rad
Angle ∠ B = β = 23.62993777307° = 23°37'46″ = 0.41224104416 rad
Angle ∠ C = γ = 37.87549836511° = 37°52'30″ = 0.66110431689 rad

Height: ha = 3.13304951685
Height: hb = 6.86440647298
Height: hc = 4.48112907977

Median: ma = 3.5
Median: mb = 9.30105376189
Median: mc = 7.76220873481

Inradius: r = 1.45329085918
Circumradius: R = 6.36107533888

Vertex coordinates: A[-3; -4] B[-8; 2] C[2; -3]
Centroid: CG[-3; -1.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[3.3210933924; 1.45329085918]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 61.50443613818° = 61°30'16″ = 2.06881390431 rad
∠ B' = β' = 156.3710622269° = 156°22'14″ = 0.41224104416 rad
∠ C' = γ' = 142.1255016349° = 142°7'30″ = 0.66110431689 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     