# 8 18 22 triangle

### Obtuse scalene triangle.

Sides: a = 8   b = 18   c = 22

Area: T = 67.88222509939
Perimeter: p = 48
Semiperimeter: s = 24

Angle ∠ A = α = 20.05499757242° = 20°3' = 0.35499380913 rad
Angle ∠ B = β = 50.47988036414° = 50°28'44″ = 0.8811021326 rad
Angle ∠ C = γ = 109.4711220634° = 109°28'16″ = 1.91106332362 rad

Height: ha = 16.97105627485
Height: hb = 7.54224723327
Height: hc = 6.17111137267

Median: ma = 19.69877156036
Median: mb = 13.89224439894
Median: mc = 8.54440037453

Inradius: r = 2.82884271247
Circumradius: R = 11.66772618896

Vertex coordinates: A[22; 0] B[0; 0] C[5.09109090909; 6.17111137267]
Centroid: CG[9.03303030303; 2.05770379089]
Coordinates of the circumscribed circle: U[11; -3.88990872965]
Coordinates of the inscribed circle: I[6; 2.82884271247]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 159.9550024276° = 159°57' = 0.35499380913 rad
∠ B' = β' = 129.5211196359° = 129°31'16″ = 0.8811021326 rad
∠ C' = γ' = 70.52987793655° = 70°31'44″ = 1.91106332362 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.