# 1.5 3.6 3.9 triangle

### Right scalene triangle.

Sides: a = 1.5   b = 3.6   c = 3.9

Area: T = 2.7
Perimeter: p = 9
Semiperimeter: s = 4.5

Angle ∠ A = α = 22.6219864948° = 22°37'11″ = 0.39547911197 rad
Angle ∠ B = β = 67.3880135052° = 67°22'49″ = 1.17660052071 rad
Angle ∠ C = γ = 90° = 1.57107963268 rad

Height: ha = 3.6
Height: hb = 1.5
Height: hc = 1.38546153846

Median: ma = 3.67772952016
Median: mb = 2.34330749028
Median: mc = 1.95

Vertex coordinates: A[3.9; 0] B[0; 0] C[0.57769230769; 1.38546153846]
Centroid: CG[1.49223076923; 0.46215384615]
Coordinates of the circumscribed circle: U[1.95; 0]
Coordinates of the inscribed circle: I[0.9; 0.6]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 157.3880135052° = 157°22'49″ = 0.39547911197 rad
∠ B' = β' = 112.6219864948° = 112°37'11″ = 1.17660052071 rad
∠ C' = γ' = 90° = 1.57107963268 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    