# 12 19 26 triangle

### Obtuse scalene triangle.

Sides: a = 12   b = 19   c = 26

Area: T = 105.6810828441
Perimeter: p = 57
Semiperimeter: s = 28.5

Angle ∠ A = α = 25.33216750167° = 25°19'54″ = 0.44221211341 rad
Angle ∠ B = β = 42.64440121462° = 42°38'38″ = 0.74442784182 rad
Angle ∠ C = γ = 112.0244312837° = 112°1'28″ = 1.95551931013 rad

Height: ha = 17.61334714069
Height: hb = 11.12442977306
Height: hc = 8.12992944955

Median: ma = 21.96658826365
Median: mb = 17.88215547422
Median: mc = 9.13878334412

Inradius: r = 3.70880992435
Circumradius: R = 14.02333571392

Vertex coordinates: A[26; 0] B[0; 0] C[8.82769230769; 8.12992944955]
Centroid: CG[11.6098974359; 2.71097648318]
Coordinates of the circumscribed circle: U[13; -5.25987589272]
Coordinates of the inscribed circle: I[9.5; 3.70880992435]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 154.6688324983° = 154°40'6″ = 0.44221211341 rad
∠ B' = β' = 137.3565987854° = 137°21'22″ = 0.74442784182 rad
∠ C' = γ' = 67.9765687163° = 67°58'32″ = 1.95551931013 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.