# 2 11 12 triangle

### Obtuse scalene triangle.

Sides: a = 2   b = 11   c = 12

Area: T = 9.92215674165
Perimeter: p = 25
Semiperimeter: s = 12.5

Angle ∠ A = α = 8.64658643504° = 8°38'45″ = 0.15108987996 rad
Angle ∠ B = β = 55.77111336722° = 55°46'16″ = 0.97333899101 rad
Angle ∠ C = γ = 115.5833001977° = 115°34'59″ = 2.01773039438 rad

Height: ha = 9.92215674165
Height: hb = 1.80439213485
Height: hc = 1.65435945694

Median: ma = 11.46773449412
Median: mb = 6.61443782777
Median: mc = 5.14878150705

Inradius: r = 0.79437253933
Circumradius: R = 6.6522174725

Vertex coordinates: A[12; 0] B[0; 0] C[1.125; 1.65435945694]
Centroid: CG[4.375; 0.55111981898]
Coordinates of the circumscribed circle: U[6; -2.87325299949]
Coordinates of the inscribed circle: I[1.5; 0.79437253933]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 171.354413565° = 171°21'15″ = 0.15108987996 rad
∠ B' = β' = 124.2298866328° = 124°13'44″ = 0.97333899101 rad
∠ C' = γ' = 64.41769980226° = 64°25'1″ = 2.01773039438 rad

# How did we calculate this triangle?

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. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.