# 11 26 26 triangle

### Acute isosceles triangle.

Sides: a = 11   b = 26   c = 26

Area: T = 139.7643863355
Perimeter: p = 63
Semiperimeter: s = 31.5

Angle ∠ A = α = 24.42550505378° = 24°25'30″ = 0.42662975519 rad
Angle ∠ B = β = 77.78774747311° = 77°47'15″ = 1.35876475509 rad
Angle ∠ C = γ = 77.78774747311° = 77°47'15″ = 1.35876475509 rad

Height: ha = 25.41216115191
Height: hb = 10.75110664119
Height: hc = 10.75110664119

Median: ma = 25.41216115191
Median: mb = 15.14992574075
Median: mc = 15.14992574075

Inradius: r = 4.4376948043
Circumradius: R = 13.30110061068

Vertex coordinates: A[26; 0] B[0; 0] C[2.32769230769; 10.75110664119]
Centroid: CG[9.44223076923; 3.5843688804]
Coordinates of the circumscribed circle: U[13; 2.81436743687]
Coordinates of the inscribed circle: I[5.5; 4.4376948043]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 155.5754949462° = 155°34'30″ = 0.42662975519 rad
∠ B' = β' = 102.2132525269° = 102°12'45″ = 1.35876475509 rad
∠ C' = γ' = 102.2132525269° = 102°12'45″ = 1.35876475509 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.