# 12 16 23 triangle

### Obtuse scalene triangle.

Sides: a = 12   b = 16   c = 23

Area: T = 90.42108908383
Perimeter: p = 51
Semiperimeter: s = 25.5

Angle ∠ A = α = 29.43438177134° = 29°26'2″ = 0.51437170305 rad
Angle ∠ B = β = 40.93766253727° = 40°56'12″ = 0.71444788974 rad
Angle ∠ C = γ = 109.6329556914° = 109°37'46″ = 1.91333967257 rad

Height: ha = 15.07701484731
Height: hb = 11.30326113548
Height: hc = 7.86326861599

Median: ma = 18.88112075885
Median: mb = 16.50875740192
Median: mc = 8.23110388166

Inradius: r = 3.54659172878
Circumradius: R = 12.21095678307

Vertex coordinates: A[23; 0] B[0; 0] C[9.06552173913; 7.86326861599]
Centroid: CG[10.68884057971; 2.62108953866]
Coordinates of the circumscribed circle: U[11.5; -4.10216516931]
Coordinates of the inscribed circle: I[9.5; 3.54659172878]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 150.5666182287° = 150°33'58″ = 0.51437170305 rad
∠ B' = β' = 139.0633374627° = 139°3'48″ = 0.71444788974 rad
∠ C' = γ' = 70.37704430861° = 70°22'14″ = 1.91333967257 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.