# 12 26 27 triangle

### Acute scalene triangle.

Sides: a = 12   b = 26   c = 27

Area: T = 154.3322230918
Perimeter: p = 65
Semiperimeter: s = 32.5

Angle ∠ A = α = 26.08442927774° = 26°5'3″ = 0.4555256792 rad
Angle ∠ B = β = 72.30112458697° = 72°18'4″ = 1.26218947937 rad
Angle ∠ C = γ = 81.61444613529° = 81°36'52″ = 1.42444410679 rad

Height: ha = 25.72220384863
Height: hb = 11.87217100706
Height: hc = 11.4322017105

Median: ma = 25.81766612869
Median: mb = 16.35554272338
Median: mc = 15.09113882728

Inradius: r = 4.74986840282
Circumradius: R = 13.64658858106

Vertex coordinates: A[27; 0] B[0; 0] C[3.64881481481; 11.4322017105]
Centroid: CG[10.21660493827; 3.81106723683]
Coordinates of the circumscribed circle: U[13.5; 1.9990025014]
Coordinates of the inscribed circle: I[6.5; 4.74986840282]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 153.9165707223° = 153°54'57″ = 0.4555256792 rad
∠ B' = β' = 107.699875413° = 107°41'55″ = 1.26218947937 rad
∠ C' = γ' = 98.38655386471° = 98°23'8″ = 1.42444410679 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.