# 10 22 26 triangle

### Obtuse scalene triangle.

Sides: a = 10   b = 22   c = 26

Area: T = 107.5698582774
Perimeter: p = 58
Semiperimeter: s = 29

Angle ∠ A = α = 22.09331769923° = 22°5'35″ = 0.38655986807 rad
Angle ∠ B = β = 55.83877404834° = 55°50'16″ = 0.97545524183 rad
Angle ∠ C = γ = 102.0699082524° = 102°4'9″ = 1.78114415545 rad

Height: ha = 21.51437165548
Height: hb = 9.77989620704
Height: hc = 8.27545063672

Median: ma = 23.55884379788
Median: mb = 16.34401346384
Median: mc = 11.09105365064

Inradius: r = 3.7099261475
Circumradius: R = 13.2943844384

Vertex coordinates: A[26; 0] B[0; 0] C[5.61553846154; 8.27545063672]
Centroid: CG[10.53884615385; 2.75881687891]
Coordinates of the circumscribed circle: U[13; -2.78796220076]
Coordinates of the inscribed circle: I[7; 3.7099261475]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 157.9076823008° = 157°54'25″ = 0.38655986807 rad
∠ B' = β' = 124.1622259517° = 124°9'44″ = 0.97545524183 rad
∠ C' = γ' = 77.93109174756° = 77°55'51″ = 1.78114415545 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    