# 18 19 27 triangle

### Obtuse scalene triangle.

Sides: a = 18   b = 19   c = 27

Area: T = 170.6465832062
Perimeter: p = 64
Semiperimeter: s = 32

Angle ∠ A = α = 41.70442622138° = 41°42'15″ = 0.72878766877 rad
Angle ∠ B = β = 44.60774977068° = 44°36'27″ = 0.77985477061 rad
Angle ∠ C = γ = 93.68882400795° = 93°41'18″ = 1.63551682598 rad

Height: ha = 18.96106480068
Height: hb = 17.96327191644
Height: hc = 12.64404320046

Median: ma = 21.54106592285
Median: mb = 20.88765985742
Median: mc = 12.65989889012

Inradius: r = 5.33326822519
Circumradius: R = 13.52880186578

Vertex coordinates: A[27; 0] B[0; 0] C[12.81548148148; 12.64404320046]
Centroid: CG[13.27216049383; 4.21334773349]
Coordinates of the circumscribed circle: U[13.5; -0.87702234224]
Coordinates of the inscribed circle: I[13; 5.33326822519]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 138.2965737786° = 138°17'45″ = 0.72878766877 rad
∠ B' = β' = 135.3932502293° = 135°23'33″ = 0.77985477061 rad
∠ C' = γ' = 86.31217599205° = 86°18'42″ = 1.63551682598 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.