# 13 18 22 triangle

### Acute scalene triangle.

Sides: a = 13   b = 18   c = 22

Area: T = 116.9788363384
Perimeter: p = 53
Semiperimeter: s = 26.5

Angle ∠ A = α = 36.21437860673° = 36°12'50″ = 0.63220498015 rad
Angle ∠ B = β = 54.8888123772° = 54°53'17″ = 0.95879784801 rad
Angle ∠ C = γ = 88.89880901607° = 88°53'53″ = 1.5521564372 rad

Height: ha = 17.99766712898
Height: hb = 12.99875959316
Height: hc = 10.63443966713

Median: ma = 19.02197266016
Median: mb = 15.6688439616
Median: mc = 11.20326782512

Inradius: r = 4.41442778635
Circumradius: R = 11.0022034588

Vertex coordinates: A[22; 0] B[0; 0] C[7.47772727273; 10.63443966713]
Centroid: CG[9.82657575758; 3.54547988904]
Coordinates of the circumscribed circle: U[11; 0.21215775882]
Coordinates of the inscribed circle: I[8.5; 4.41442778635]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 143.7866213933° = 143°47'10″ = 0.63220498015 rad
∠ B' = β' = 125.1121876228° = 125°6'43″ = 0.95879784801 rad
∠ C' = γ' = 91.10219098393° = 91°6'7″ = 1.5521564372 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.