# 9 18 19 triangle

### Acute scalene triangle.

Sides: a = 9   b = 18   c = 19

Area: T = 80.2549610591
Perimeter: p = 46
Semiperimeter: s = 23

Angle ∠ A = α = 27.989860602° = 27°59'19″ = 0.48884933281 rad
Angle ∠ B = β = 69.81664193194° = 69°48'59″ = 1.21985263891 rad
Angle ∠ C = γ = 82.19549746606° = 82°11'42″ = 1.43545729364 rad

Height: ha = 17.8333246798
Height: hb = 8.9176623399
Height: hc = 8.44773274306

Median: ma = 17.9511323071
Median: mb = 11.83221595662
Median: mc = 10.59548100502

Inradius: r = 3.4899113504
Circumradius: R = 9.5898831576

Vertex coordinates: A[19; 0] B[0; 0] C[3.10552631579; 8.44773274306]
Centroid: CG[7.36884210526; 2.81657758102]
Coordinates of the circumscribed circle: U[9.5; 1.30221870042]
Coordinates of the inscribed circle: I[5; 3.4899113504]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 152.011139398° = 152°41″ = 0.48884933281 rad
∠ B' = β' = 110.1843580681° = 110°11'1″ = 1.21985263891 rad
∠ C' = γ' = 97.80550253394° = 97°48'18″ = 1.43545729364 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 ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.