# 8 18 24 triangle

### Obtuse scalene triangle.

Sides: a = 8   b = 18   c = 24

Area: T = 54.54435605732
Perimeter: p = 50
Semiperimeter: s = 25

Angle ∠ A = α = 14.62664748646° = 14°37'35″ = 0.25552801443 rad
Angle ∠ B = β = 34.62221618397° = 34°37'20″ = 0.60442707183 rad
Angle ∠ C = γ = 130.7511363296° = 130°45'5″ = 2.2822041791 rad

Height: ha = 13.63658901433
Height: hb = 6.06603956192
Height: hc = 4.54552967144

Median: ma = 20.8332666656
Median: mb = 15.46596248337
Median: mc = 7.07110678119

Inradius: r = 2.18217424229
Circumradius: R = 15.84105500286

Vertex coordinates: A[24; 0] B[0; 0] C[6.58333333333; 4.54552967144]
Centroid: CG[10.19444444444; 1.51550989048]
Coordinates of the circumscribed circle: U[12; -10.34403590465]
Coordinates of the inscribed circle: I[7; 2.18217424229]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 165.3743525135° = 165°22'25″ = 0.25552801443 rad
∠ B' = β' = 145.378783816° = 145°22'40″ = 0.60442707183 rad
∠ C' = γ' = 49.24986367043° = 49°14'55″ = 2.2822041791 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    