# 14 18 20 triangle

### Acute scalene triangle.

Sides: a = 14   b = 18   c = 20

Area: T = 122.3766468326
Perimeter: p = 52
Semiperimeter: s = 26

Angle ∠ A = α = 42.83334280661° = 42°50' = 0.74875843497 rad
Angle ∠ B = β = 60.9410718932° = 60°56'27″ = 1.06436161939 rad
Angle ∠ C = γ = 76.2265853002° = 76°13'33″ = 1.333039211 rad

Height: ha = 17.4822352618
Height: hb = 13.59773853696
Height: hc = 12.23876468326

Median: ma = 17.6921806013
Median: mb = 14.73109198627
Median: mc = 12.64991106407

Inradius: r = 4.70767872433
Circumradius: R = 10.29660970948

Vertex coordinates: A[20; 0] B[0; 0] C[6.8; 12.23876468326]
Centroid: CG[8.93333333333; 4.07992156109]
Coordinates of the circumscribed circle: U[10; 2.45114516892]
Coordinates of the inscribed circle: I[8; 4.70767872433]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 137.1676571934° = 137°10' = 0.74875843497 rad
∠ B' = β' = 119.0599281068° = 119°3'33″ = 1.06436161939 rad
∠ C' = γ' = 103.7744146998° = 103°46'27″ = 1.333039211 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.