# Triangle calculator VC

Please enter the coordinates of the three vertices

### Obtuse scalene triangle.

Sides: a = 15.7911041036   b = 13.43995994716   c = 28.79327473681

Area: T = 34.45552145004
Perimeter: p = 57.98333878757
Semiperimeter: s = 28.99216939379

Angle ∠ A = α = 10.28989087095° = 10°17'20″ = 0.18795753334 rad
Angle ∠ B = β = 8.71774729185° = 8°43'3″ = 0.15221486049 rad
Angle ∠ C = γ = 160.9943618372° = 160°59'37″ = 2.81098687153 rad

Height: ha = 4.36438939854
Height: hb = 5.14327230453
Height: hc = 2.39333259345

Median: ma = 21.02325245689
Median: mb = 22.23329107969
Median: mc = 2.68328243047

Vertex coordinates: A[401057.786; 487138.255] B[401029.316; 487142.554] C[401045.107; 487142.59]
Centroid: CG[401044.0769667; 487141.133]
Coordinates of the circumscribed circle: U[0; 0]
Coordinates of the inscribed circle: I[7.75107545258; 1.18884512362]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 169.711109129° = 169°42'40″ = 0.18795753334 rad
∠ B' = β' = 171.2832527082° = 171°16'57″ = 0.15221486049 rad
∠ C' = γ' = 19.0066381628° = 19°23″ = 2.81098687153 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    