# 12 12 22 triangle

### Obtuse isosceles triangle.

Sides: a = 12   b = 12   c = 22

Area: T = 52.75441467564
Perimeter: p = 46
Semiperimeter: s = 23

Angle ∠ A = α = 23.55664643091° = 23°33'23″ = 0.41111378623 rad
Angle ∠ B = β = 23.55664643091° = 23°33'23″ = 0.41111378623 rad
Angle ∠ C = γ = 132.8877071382° = 132°53'13″ = 2.31993169289 rad

Height: ha = 8.79223577927
Height: hb = 8.79223577927
Height: hc = 4.79658315233

Median: ma = 16.67333320005
Median: mb = 16.67333320005
Median: mc = 4.79658315233

Inradius: r = 2.29436585546
Circumradius: R = 15.01330378121

Vertex coordinates: A[22; 0] B[0; 0] C[11; 4.79658315233]
Centroid: CG[11; 1.59986105078]
Coordinates of the circumscribed circle: U[11; -10.21772062888]
Coordinates of the inscribed circle: I[11; 2.29436585546]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 156.4443535691° = 156°26'37″ = 0.41111378623 rad
∠ B' = β' = 156.4443535691° = 156°26'37″ = 0.41111378623 rad
∠ C' = γ' = 47.11329286182° = 47°6'47″ = 2.31993169289 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.