# 16 18 22 triangle

### Acute scalene triangle.

Sides: a = 16   b = 18   c = 22

Area: T = 141.9865914794
Perimeter: p = 56
Semiperimeter: s = 28

Angle ∠ A = α = 45.81656148467° = 45°48'56″ = 0.87996333279 rad
Angle ∠ B = β = 53.77884533802° = 53°46'42″ = 0.93986110781 rad
Angle ∠ C = γ = 80.40659317731° = 80°24'21″ = 1.40333482476 rad

Height: ha = 17.74882393493
Height: hb = 15.77662127549
Height: hc = 12.90878104359

Median: ma = 18.43990889146
Median: mb = 17
Median: mc = 13

Inradius: r = 5.07109255284
Circumradius: R = 11.15660361624

Vertex coordinates: A[22; 0] B[0; 0] C[9.45545454545; 12.90878104359]
Centroid: CG[10.48548484848; 4.30326034786]
Coordinates of the circumscribed circle: U[11; 1.85993393604]
Coordinates of the inscribed circle: I[10; 5.07109255284]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 134.1844385153° = 134°11'4″ = 0.87996333279 rad
∠ B' = β' = 126.222154662° = 126°13'18″ = 0.93986110781 rad
∠ C' = γ' = 99.59440682269° = 99°35'39″ = 1.40333482476 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    