# 9 25 27 triangle

### Obtuse scalene triangle.

Sides: a = 9   b = 25   c = 27

Area: T = 112.3532959463
Perimeter: p = 61
Semiperimeter: s = 30.5

Angle ∠ A = α = 19.44547461971° = 19°26'41″ = 0.33993748434 rad
Angle ∠ B = β = 67.62655263278° = 67°37'32″ = 1.18802880928 rad
Angle ∠ C = γ = 92.93297274751° = 92°55'47″ = 1.62219297174 rad

Height: ha = 24.9677324325
Height: hb = 8.9888236757
Height: hc = 8.32224414417

Median: ma = 25.62771340575
Median: mb = 15.77218102956
Median: mc = 13.06771343454

Inradius: r = 3.68437035889
Circumradius: R = 13.5187667957

Vertex coordinates: A[27; 0] B[0; 0] C[3.42659259259; 8.32224414417]
Centroid: CG[10.14219753086; 2.77441471472]
Coordinates of the circumscribed circle: U[13.5; -0.69109030289]
Coordinates of the inscribed circle: I[5.5; 3.68437035889]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 160.5555253803° = 160°33'19″ = 0.33993748434 rad
∠ B' = β' = 112.3744473672° = 112°22'28″ = 1.18802880928 rad
∠ C' = γ' = 87.07702725249° = 87°4'13″ = 1.62219297174 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    