Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse scalene triangle.

Sides: a = 4.89989794856   b = 9.43439811321   c = 4.5832575695

Area: T = 2.23660679775
Perimeter: p = 18.91655363126
Semiperimeter: s = 9.45877681563

Angle ∠ A = α = 5.93875953156° = 5°56'15″ = 0.10436305879 rad
Angle ∠ B = β = 168.5109540096° = 168°30'34″ = 2.94110462957 rad
Angle ∠ C = γ = 5.55328645881° = 5°33'10″ = 0.097691577 rad

Height: ha = 0.91328709292
Height: hb = 0.47440454631
Height: hc = 0.97659000729

Median: ma = 7
Median: mb = 0.5
Median: mc = 7.15989105316

Inradius: r = 0.23664266009
Circumradius: R = 23.67991047128

Vertex coordinates: A[2; -3; 5] B[0; 1; 4] C[-2; 5; 2]
Centroid: CG[0; 1; 3.66766666667]
Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 174.0622404684° = 174°3'45″ = 0.10436305879 rad
∠ B' = β' = 11.49904599037° = 11°29'26″ = 2.94110462957 rad
∠ C' = γ' = 174.4477135412° = 174°26'50″ = 0.097691577 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     