# 9 13 14 triangle

### Acute scalene triangle.

Sides: a = 9   b = 13   c = 14

Area: T = 56.9210997883
Perimeter: p = 36
Semiperimeter: s = 18

Angle ∠ A = α = 38.71992973222° = 38°43'9″ = 0.67657792223 rad
Angle ∠ B = β = 64.62330664748° = 64°37'23″ = 1.12878852827 rad
Angle ∠ C = γ = 76.65876362029° = 76°39'28″ = 1.33879281485 rad

Height: ha = 12.64991106407
Height: hb = 8.75770765974
Height: hc = 8.13215711261

Median: ma = 12.73877392029
Median: mb = 9.81107084352
Median: mc = 8.71877978871

Inradius: r = 3.16222776602
Circumradius: R = 7.19441816769

Vertex coordinates: A[14; 0] B[0; 0] C[3.85771428571; 8.13215711261]
Centroid: CG[5.95223809524; 2.71105237087]
Coordinates of the circumscribed circle: U[7; 1.66601957716]
Coordinates of the inscribed circle: I[5; 3.16222776602]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 141.2810702678° = 141°16'51″ = 0.67657792223 rad
∠ B' = β' = 115.3776933525° = 115°22'37″ = 1.12878852827 rad
∠ C' = γ' = 103.3422363797° = 103°20'32″ = 1.33879281485 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    