# 2.4 4.5 5.2 triangle

### Obtuse scalene triangle.

Sides: a = 2.4   b = 4.5   c = 5.2

Area: T = 5.39438570383
Perimeter: p = 12.1
Semiperimeter: s = 6.05

Angle ∠ A = α = 27.45325211305° = 27°27'9″ = 0.47991368817 rad
Angle ∠ B = β = 59.81442825197° = 59°48'51″ = 1.04439561697 rad
Angle ∠ C = γ = 92.73331963499° = 92°44' = 1.61884996022 rad

Height: ha = 4.49548808653
Height: hb = 2.39772697948
Height: hc = 2.07545603994

Median: ma = 4.71222181613
Median: mb = 3.36771204315
Median: mc = 2.49989997999

Inradius: r = 0.89215466179
Circumradius: R = 2.60329610908

Vertex coordinates: A[5.2; 0] B[0; 0] C[1.20767307692; 2.07545603994]
Centroid: CG[2.13655769231; 0.69215201331]
Coordinates of the circumscribed circle: U[2.6; -0.12441226816]
Coordinates of the inscribed circle: I[1.55; 0.89215466179]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 152.547747887° = 152°32'51″ = 0.47991368817 rad
∠ B' = β' = 120.186571748° = 120°11'9″ = 1.04439561697 rad
∠ C' = γ' = 87.26768036501° = 87°16' = 1.61884996022 rad

# How did we calculate this triangle?

### 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    