# 12 17 23 triangle

### Obtuse scalene triangle.

Sides: a = 12   b = 17   c = 23

Area: T = 99.13662698511
Perimeter: p = 52
Semiperimeter: s = 26

Angle ∠ A = α = 30.47702492171° = 30°28'13″ = 0.53218061727 rad
Angle ∠ B = β = 45.92107901521° = 45°55'15″ = 0.80114689833 rad
Angle ∠ C = γ = 103.6098960631° = 103°36'32″ = 1.80883174976 rad

Height: ha = 16.52327116419
Height: hb = 11.66330905707
Height: hc = 8.62105452044

Median: ma = 19.31332079158
Median: mb = 16.2565768207
Median: mc = 9.17987798753

Inradius: r = 3.81329334558
Circumradius: R = 11.83221982637

Vertex coordinates: A[23; 0] B[0; 0] C[8.3487826087; 8.62105452044]
Centroid: CG[10.44992753623; 2.87435150681]
Coordinates of the circumscribed circle: U[11.5; -2.78440466503]
Coordinates of the inscribed circle: I[9; 3.81329334558]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 149.5329750783° = 149°31'47″ = 0.53218061727 rad
∠ B' = β' = 134.0799209848° = 134°4'45″ = 0.80114689833 rad
∠ C' = γ' = 76.39110393692° = 76°23'28″ = 1.80883174976 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.