# 5 11 11 triangle

### Acute isosceles triangle.

Sides: a = 5   b = 11   c = 11

Area: T = 26.7880356607
Perimeter: p = 27
Semiperimeter: s = 13.5

Angle ∠ A = α = 26.27331175739° = 26°16'23″ = 0.45985524064 rad
Angle ∠ B = β = 76.86334412131° = 76°51'48″ = 1.34215201236 rad
Angle ∠ C = γ = 76.86334412131° = 76°51'48″ = 1.34215201236 rad

Height: ha = 10.71221426428
Height: hb = 4.86991557467
Height: hc = 4.86991557467

Median: ma = 10.71221426428
Median: mb = 6.53883484153
Median: mc = 6.53883484153

Inradius: r = 1.9843730119
Circumradius: R = 5.64877963389

Vertex coordinates: A[11; 0] B[0; 0] C[1.13663636364; 4.86991557467]
Centroid: CG[4.04554545455; 1.62330519156]
Coordinates of the circumscribed circle: U[5.5; 1.2843590077]
Coordinates of the inscribed circle: I[2.5; 1.9843730119]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 153.7276882426° = 153°43'37″ = 0.45985524064 rad
∠ B' = β' = 103.1376558787° = 103°8'12″ = 1.34215201236 rad
∠ C' = γ' = 103.1376558787° = 103°8'12″ = 1.34215201236 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.