# 26 26 30 triangle

### Acute isosceles triangle.

Sides: a = 26   b = 26   c = 30

Area: T = 318.5511408724
Perimeter: p = 82
Semiperimeter: s = 41

Angle ∠ A = α = 54.76655820154° = 54°45'56″ = 0.95658397229 rad
Angle ∠ B = β = 54.76655820154° = 54°45'56″ = 0.95658397229 rad
Angle ∠ C = γ = 70.46988359692° = 70°28'8″ = 1.23299132077 rad

Height: ha = 24.50439545172
Height: hb = 24.50439545172
Height: hc = 21.23767605816

Median: ma = 24.88797106092
Median: mb = 24.88797106092
Median: mc = 21.23767605816

Inradius: r = 7.77695465542
Circumradius: R = 15.9165798396

Vertex coordinates: A[30; 0] B[0; 0] C[15; 21.23767605816]
Centroid: CG[15; 7.07989201939]
Coordinates of the circumscribed circle: U[15; 5.32109621856]
Coordinates of the inscribed circle: I[15; 7.77695465542]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 125.2344417985° = 125°14'4″ = 0.95658397229 rad
∠ B' = β' = 125.2344417985° = 125°14'4″ = 0.95658397229 rad
∠ C' = γ' = 109.5311164031° = 109°31'52″ = 1.23299132077 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.