# 7 9 14 triangle

### Obtuse scalene triangle.

Sides: a = 7   b = 9   c = 14

Area: T = 26.833281573
Perimeter: p = 30
Semiperimeter: s = 15

Angle ∠ A = α = 25.20987652968° = 25°12'32″ = 0.44399759548 rad
Angle ∠ B = β = 33.2033099198° = 33°12'11″ = 0.58795034029 rad
Angle ∠ C = γ = 121.5888135505° = 121°35'17″ = 2.12221132959 rad

Height: ha = 7.667651878
Height: hb = 5.963284794
Height: hc = 3.833325939

Median: ma = 11.23661025271
Median: mb = 10.11218742081
Median: mc = 4

Inradius: r = 1.7898854382
Circumradius: R = 8.21875498173

Vertex coordinates: A[14; 0] B[0; 0] C[5.85771428571; 3.833325939]
Centroid: CG[6.6199047619; 1.278775313]
Coordinates of the circumscribed circle: U[7; -4.30444308567]
Coordinates of the inscribed circle: I[6; 1.7898854382]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 154.7911234703° = 154°47'28″ = 0.44399759548 rad
∠ B' = β' = 146.7976900802° = 146°47'49″ = 0.58795034029 rad
∠ C' = γ' = 58.41218644948° = 58°24'43″ = 2.12221132959 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    