# 2.5 2.5 4.5 triangle

### Obtuse isosceles triangle.

Sides: a = 2.5   b = 2.5   c = 4.5

Area: T = 2.45218806557
Perimeter: p = 9.5
Semiperimeter: s = 4.75

Angle ∠ A = α = 25.84219327632° = 25°50'31″ = 0.45110268118 rad
Angle ∠ B = β = 25.84219327632° = 25°50'31″ = 0.45110268118 rad
Angle ∠ C = γ = 128.3166134474° = 128°18'58″ = 2.243953903 rad

Height: ha = 1.96215045246
Height: hb = 1.96215045246
Height: hc = 1.09897247359

Median: ma = 3.41986985828
Median: mb = 3.41986985828
Median: mc = 1.09897247359

Inradius: r = 0.51661854012
Circumradius: R = 2.86876966734

Vertex coordinates: A[4.5; 0] B[0; 0] C[2.25; 1.09897247359]
Centroid: CG[2.25; 0.36332415786]
Coordinates of the circumscribed circle: U[2.25; -1.77879719375]
Coordinates of the inscribed circle: I[2.25; 0.51661854012]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 154.1588067237° = 154°9'29″ = 0.45110268118 rad
∠ B' = β' = 154.1588067237° = 154°9'29″ = 0.45110268118 rad
∠ C' = γ' = 51.68438655263° = 51°41'2″ = 2.243953903 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.