# 11 20 26 triangle

### Obtuse scalene triangle.

Sides: a = 11   b = 20   c = 26

Area: T = 102.9498712959
Perimeter: p = 57
Semiperimeter: s = 28.5

Angle ∠ A = α = 23.32656473866° = 23°19'32″ = 0.40771093471 rad
Angle ∠ B = β = 46.04879641864° = 46°2'53″ = 0.80436885889 rad
Angle ∠ C = γ = 110.6266388427° = 110°37'35″ = 1.93107947176 rad

Height: ha = 18.71879478108
Height: hb = 10.29548712959
Height: hc = 7.91991317661

Median: ma = 22.53333086785
Median: mb = 17.27771525432
Median: mc = 9.56655632349

Inradius: r = 3.61222355424
Circumradius: R = 13.89904116321

Vertex coordinates: A[26; 0] B[0; 0] C[7.63546153846; 7.91991317661]
Centroid: CG[11.21215384615; 2.64397105887]
Coordinates of the circumscribed circle: U[13; -4.89332131886]
Coordinates of the inscribed circle: I[8.5; 3.61222355424]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 156.6744352613° = 156°40'28″ = 0.40771093471 rad
∠ B' = β' = 133.9522035814° = 133°57'7″ = 0.80436885889 rad
∠ C' = γ' = 69.3743611573° = 69°22'25″ = 1.93107947176 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.