Triangle calculator VC

Please enter the coordinates of the three vertices

Acute scalene triangle.

Sides: a = 6.70882039325   b = 5.09990195136   c = 7.28801098893

Area: T = 16.5
Perimeter: p = 19.08773333354
Semiperimeter: s = 9.54436666677

Angle ∠ A = α = 62.74546716251° = 62°44'41″ = 1.09551011079 rad
Angle ∠ B = β = 42.5110447078° = 42°30'38″ = 0.7421947268 rad
Angle ∠ C = γ = 74.74548812969° = 74°44'42″ = 1.30545442776 rad

Height: ha = 4.91993495505
Height: hb = 6.47218324596
Height: hc = 4.53328986103

Median: ma = 5.31550729064
Median: mb = 6.51992024052
Median: mc = 4.7176990566

Inradius: r = 1.72988952532
Circumradius: R = 3.77330010854

Vertex coordinates: A[-2; -2] B[0; 5] C[3; -1]
Centroid: CG[0.33333333333; 0.66766666667]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[1.8866067549; 1.72988952532]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 117.2555328375° = 117°15'19″ = 1.09551011079 rad
∠ B' = β' = 137.4989552922° = 137°29'22″ = 0.7421947268 rad
∠ C' = γ' = 105.2555118703° = 105°15'18″ = 1.30545442776 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     