Triangle calculator VC

Please enter the coordinates of the three vertices

Obtuse isosceles triangle.

Sides: a = 10.05498756211   b = 10.05498756211   c = 15.55663491861

Area: T = 49.5
Perimeter: p = 35.65661004283
Semiperimeter: s = 17.82880502142

Angle ∠ A = α = 39.28994068625° = 39°17'22″ = 0.68657295109 rad
Angle ∠ B = β = 39.28994068625° = 39°17'22″ = 0.68657295109 rad
Angle ∠ C = γ = 101.4211186275° = 101°25'16″ = 1.77701336318 rad

Height: ha = 9.85108681831
Height: hb = 9.85108681831
Height: hc = 6.36439610307

Median: ma = 12.09333866224
Median: mb = 12.09333866224
Median: mc = 6.36439610307

Vertex coordinates: A[7; -2] B[-4; 9] C[-3; -1]
Centroid: CG[0; 2]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[3.39435286963; 2.77765234788]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140.7110593137° = 140°42'38″ = 0.68657295109 rad
∠ B' = β' = 140.7110593137° = 140°42'38″ = 0.68657295109 rad
∠ C' = γ' = 78.5798813725° = 78°34'44″ = 1.77701336318 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    