# 5 13 16 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 13   c = 16

Area: T = 28.56657137142
Perimeter: p = 34
Semiperimeter: s = 17

Angle ∠ A = α = 15.94223686056° = 15°56'33″ = 0.27882468227 rad
Angle ∠ B = β = 45.57329959992° = 45°34'23″ = 0.79553988302 rad
Angle ∠ C = γ = 118.4854635395° = 118°29'5″ = 2.06879470007 rad

Height: ha = 11.42662854857
Height: hb = 4.39547251868
Height: hc = 3.57107142143

Median: ma = 14.36114066163
Median: mb = 9.91221138008
Median: mc = 5.74545626465

Inradius: r = 1.68803361008
Circumradius: R = 9.10218205462

Vertex coordinates: A[16; 0] B[0; 0] C[3.5; 3.57107142143]
Centroid: CG[6.5; 1.19902380714]
Coordinates of the circumscribed circle: U[8; -4.34108682605]
Coordinates of the inscribed circle: I[4; 1.68803361008]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 164.0587631394° = 164°3'27″ = 0.27882468227 rad
∠ B' = β' = 134.4277004001° = 134°25'37″ = 0.79553988302 rad
∠ C' = γ' = 61.51553646048° = 61°30'55″ = 2.06879470007 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.