# 6 18 23 triangle

### Obtuse scalene triangle.

Sides: a = 6   b = 18   c = 23

Area: T = 33.62994142084
Perimeter: p = 47
Semiperimeter: s = 23.5

Angle ∠ A = α = 9.3549766841° = 9°20'59″ = 0.16331842157 rad
Angle ∠ B = β = 29.16987062436° = 29°10'7″ = 0.50990899625 rad
Angle ∠ C = γ = 141.4821526915° = 141°28'54″ = 2.46993184754 rad

Height: ha = 11.21098047361
Height: hb = 3.73766015787
Height: hc = 2.92442968877

Median: ma = 20.43328167417
Median: mb = 14.19550695666
Median: mc = 6.91101374805

Inradius: r = 1.43110389025
Circumradius: R = 18.46659773183

Vertex coordinates: A[23; 0] B[0; 0] C[5.23991304348; 2.92442968877]
Centroid: CG[9.41330434783; 0.97547656292]
Coordinates of the circumscribed circle: U[11.5; -14.44879174389]
Coordinates of the inscribed circle: I[5.5; 1.43110389025]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 170.6550233159° = 170°39'1″ = 0.16331842157 rad
∠ B' = β' = 150.8311293756° = 150°49'53″ = 0.50990899625 rad
∠ C' = γ' = 38.51884730846° = 38°31'6″ = 2.46993184754 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    