Triangle calculator VC

Please enter the coordinates of the three vertices

Acute isosceles triangle.

Sides: a = 2.82884271247   b = 3.16222776602   c = 3.16222776602

Area: T = 4
Perimeter: p = 9.15329824451
Semiperimeter: s = 4.57664912225

Angle ∠ A = α = 53.13301023542° = 53°7'48″ = 0.9277295218 rad
Angle ∠ B = β = 63.43549488229° = 63°26'6″ = 1.10771487178 rad
Angle ∠ C = γ = 63.43549488229° = 63°26'6″ = 1.10771487178 rad

Height: ha = 2.82884271247
Height: hb = 2.53298221281
Height: hc = 2.53298221281

Median: ma = 2.82884271247
Median: mb = 2.55495097568
Median: mc = 2.55495097568

Inradius: r = 0.87440320489
Circumradius: R = 1.7687766953

Vertex coordinates: A[1; -1] B[2; 2] C[4; 0]
Centroid: CG[2.33333333333; 0.33333333333]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[0.43770160244; 0.87440320489]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 126.8769897646° = 126°52'12″ = 0.9277295218 rad
∠ B' = β' = 116.5655051177° = 116°33'54″ = 1.10771487178 rad
∠ C' = γ' = 116.5655051177° = 116°33'54″ = 1.10771487178 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     