# 8 22 22 triangle

### Acute isosceles triangle.

Sides: a = 8   b = 22   c = 22

Area: T = 86.53332306111
Perimeter: p = 52
Semiperimeter: s = 26

Angle ∠ A = α = 20.95113633928° = 20°57'5″ = 0.3665670274 rad
Angle ∠ B = β = 79.52443183036° = 79°31'28″ = 1.38879611898 rad
Angle ∠ C = γ = 79.52443183036° = 79°31'28″ = 1.38879611898 rad

Height: ha = 21.63333076528
Height: hb = 7.86766573283
Height: hc = 7.86766573283

Median: ma = 21.63333076528
Median: mb = 12.36993168769
Median: mc = 12.36993168769

Inradius: r = 3.32882011774
Circumradius: R = 11.18664539572

Vertex coordinates: A[22; 0] B[0; 0] C[1.45545454545; 7.86766573283]
Centroid: CG[7.81881818182; 2.62222191094]
Coordinates of the circumscribed circle: U[11; 2.03439007195]
Coordinates of the inscribed circle: I[4; 3.32882011774]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 159.0498636607° = 159°2'55″ = 0.3665670274 rad
∠ B' = β' = 100.4765681696° = 100°28'32″ = 1.38879611898 rad
∠ C' = γ' = 100.4765681696° = 100°28'32″ = 1.38879611898 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    