# 13 16 26 triangle

### Obtuse scalene triangle.

Sides: a = 13   b = 16   c = 26

Area: T = 82.93663460734
Perimeter: p = 55
Semiperimeter: s = 27.5

Angle ∠ A = α = 23.4998960633° = 23°29'56″ = 0.41101342338 rad
Angle ∠ B = β = 29.39897316548° = 29°23'23″ = 0.51329475837 rad
Angle ∠ C = γ = 127.1111307712° = 127°6'41″ = 2.21985108361 rad

Height: ha = 12.75994378574
Height: hb = 10.36770432592
Height: hc = 6.38797189287

Median: ma = 20.58551888502
Median: mb = 18.93440962288
Median: mc = 6.59554529791

Inradius: r = 3.01658671299
Circumradius: R = 16.30216586094

Vertex coordinates: A[26; 0] B[0; 0] C[11.32769230769; 6.38797189287]
Centroid: CG[12.44223076923; 2.12765729762]
Coordinates of the circumscribed circle: U[13; -9.83658565167]
Coordinates of the inscribed circle: I[11.5; 3.01658671299]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 156.5011039367° = 156°30'4″ = 0.41101342338 rad
∠ B' = β' = 150.6110268345° = 150°36'37″ = 0.51329475837 rad
∠ C' = γ' = 52.88986922878° = 52°53'19″ = 2.21985108361 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.