# 25 30 30 triangle

### Acute isosceles triangle.

Sides: a = 25   b = 30   c = 30

Area: T = 340.8977253582
Perimeter: p = 85
Semiperimeter: s = 42.5

Angle ∠ A = α = 49.24986367043° = 49°14'55″ = 0.86595508626 rad
Angle ∠ B = β = 65.37656816478° = 65°22'32″ = 1.14110208955 rad
Angle ∠ C = γ = 65.37656816478° = 65°22'32″ = 1.14110208955 rad

Height: ha = 27.27217802866
Height: hb = 22.72664835722
Height: hc = 22.72664835722

Median: ma = 27.27217802866
Median: mb = 23.18440462387
Median: mc = 23.18440462387

Inradius: r = 8.0211111849
Circumradius: R = 16.50105729465

Vertex coordinates: A[30; 0] B[0; 0] C[10.41766666667; 22.72664835722]
Centroid: CG[13.47222222222; 7.57554945241]
Coordinates of the circumscribed circle: U[15; 6.87552387277]
Coordinates of the inscribed circle: I[12.5; 8.0211111849]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 130.7511363296° = 130°45'5″ = 0.86595508626 rad
∠ B' = β' = 114.6244318352° = 114°37'28″ = 1.14110208955 rad
∠ C' = γ' = 114.6244318352° = 114°37'28″ = 1.14110208955 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.