Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 14.31878210633   b = 7.07110678119   c = 18.02877563773

Area: T = 47.5
Perimeter: p = 39.41766452525
Semiperimeter: s = 19.70883226262

Angle ∠ A = α = 48.18798301199° = 48°10'47″ = 0.84108966686 rad
Angle ∠ B = β = 21.5955310449° = 21°35'43″ = 0.37769092703 rad
Angle ∠ C = γ = 110.2254859431° = 110°13'29″ = 1.92437867146 rad

Height: ha = 6.63550878098
Height: hb = 13.43550288425
Height: hc = 5.27696518641

Median: ma = 11.67326175299
Median: mb = 15.89902485821
Median: mc = 6.80107352544

Inradius: r = 2.41101493009
Circumradius: R = 9.60661643413

Vertex coordinates: A[7; 0] B[-8; 10] C[6; 7]
Centroid: CG[1.66766666667; 5.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[6.08987982339; 2.41101493009]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 131.822016988° = 131°49'13″ = 0.84108966686 rad
∠ B' = β' = 158.4054689551° = 158°24'17″ = 0.37769092703 rad
∠ C' = γ' = 69.77551405688° = 69°46'31″ = 1.92437867146 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     