# 5 14 18 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 14   c = 18

Area: T = 23.70552209439
Perimeter: p = 37
Semiperimeter: s = 18.5

Angle ∠ A = α = 10.84440625637° = 10°50'39″ = 0.1899264596 rad
Angle ∠ B = β = 31.78883306171° = 31°47'18″ = 0.5554811033 rad
Angle ∠ C = γ = 137.3687606819° = 137°22'3″ = 2.39875170246 rad

Height: ha = 9.48220883776
Height: hb = 3.38664601348
Height: hc = 2.63439134382

Median: ma = 15.93295323221
Median: mb = 11.20326782512
Median: mc = 5.43113902456

Inradius: r = 1.28113632943
Circumradius: R = 13.28882119405

Vertex coordinates: A[18; 0] B[0; 0] C[4.25; 2.63439134382]
Centroid: CG[7.41766666667; 0.87879711461]
Coordinates of the circumscribed circle: U[9; -9.77663273563]
Coordinates of the inscribed circle: I[4.5; 1.28113632943]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 169.1565937436° = 169°9'21″ = 0.1899264596 rad
∠ B' = β' = 148.2121669383° = 148°12'42″ = 0.5554811033 rad
∠ C' = γ' = 42.63223931807° = 42°37'57″ = 2.39875170246 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.