# 25 25 26 triangle

### Acute isosceles triangle.

Sides: a = 25   b = 25   c = 26

Area: T = 277.6044034553
Perimeter: p = 76
Semiperimeter: s = 38

Angle ∠ A = α = 58.66877485024° = 58°40'4″ = 1.02439453761 rad
Angle ∠ B = β = 58.66877485024° = 58°40'4″ = 1.02439453761 rad
Angle ∠ C = γ = 62.66545029952° = 62°39'52″ = 1.09437019014 rad

Height: ha = 22.20883227642
Height: hb = 22.20883227642
Height: hc = 21.35441565041

Median: ma = 22.23217340754
Median: mb = 22.23217340754
Median: mc = 21.35441565041

Inradius: r = 7.30553693303
Circumradius: R = 14.6344153306

Vertex coordinates: A[26; 0] B[0; 0] C[13; 21.35441565041]
Centroid: CG[13; 7.1188052168]
Coordinates of the circumscribed circle: U[13; 6.72200031981]
Coordinates of the inscribed circle: I[13; 7.30553693303]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 121.3322251498° = 121°19'56″ = 1.02439453761 rad
∠ B' = β' = 121.3322251498° = 121°19'56″ = 1.02439453761 rad
∠ C' = γ' = 117.3355497005° = 117°20'8″ = 1.09437019014 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.