# 4 20 22 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 20   c = 22

Area: T = 36.20877339805
Perimeter: p = 46
Semiperimeter: s = 23

Angle ∠ A = α = 9.47328720666° = 9°28'22″ = 0.16553328072 rad
Angle ∠ B = β = 55.37664645208° = 55°22'35″ = 0.9676501634 rad
Angle ∠ C = γ = 115.1510663413° = 115°9'2″ = 2.01097582124 rad

Height: ha = 18.10438669902
Height: hb = 3.6210773398
Height: hc = 3.292161218

Median: ma = 20.92884495365
Median: mb = 12.24774487139
Median: mc = 9.32773790531

Inradius: r = 1.57442493035
Circumradius: R = 12.15220998867

Vertex coordinates: A[22; 0] B[0; 0] C[2.27327272727; 3.292161218]
Centroid: CG[8.09109090909; 1.097720406]
Coordinates of the circumscribed circle: U[11; -5.16546424518]
Coordinates of the inscribed circle: I[3; 1.57442493035]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 170.5277127933° = 170°31'38″ = 0.16553328072 rad
∠ B' = β' = 124.6243535479° = 124°37'25″ = 0.9676501634 rad
∠ C' = γ' = 64.84993365875° = 64°50'58″ = 2.01097582124 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.