# 19 26 26 triangle

### Acute isosceles triangle.

Sides: a = 19   b = 26   c = 26

Area: T = 229.9221589895
Perimeter: p = 71
Semiperimeter: s = 35.5

Angle ∠ A = α = 42.86325090077° = 42°51'45″ = 0.74880919078 rad
Angle ∠ B = β = 68.56987454962° = 68°34'7″ = 1.19767503729 rad
Angle ∠ C = γ = 68.56987454962° = 68°34'7″ = 1.19767503729 rad

Height: ha = 24.20222726206
Height: hb = 17.68662761458
Height: hc = 17.68662761458

Median: ma = 24.20222726206
Median: mb = 18.69549190958
Median: mc = 18.69549190958

Inradius: r = 6.47766645041
Circumradius: R = 13.96656306372

Vertex coordinates: A[26; 0] B[0; 0] C[6.94223076923; 17.68662761458]
Centroid: CG[10.98107692308; 5.89554253819]
Coordinates of the circumscribed circle: U[13; 5.1032826579]
Coordinates of the inscribed circle: I[9.5; 6.47766645041]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 137.1377490992° = 137°8'15″ = 0.74880919078 rad
∠ B' = β' = 111.4311254504° = 111°25'53″ = 1.19767503729 rad
∠ C' = γ' = 111.4311254504° = 111°25'53″ = 1.19767503729 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.