# 5 19 20 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 19   c = 20

Area: T = 47.37108771293
Perimeter: p = 44
Semiperimeter: s = 22

Angle ∠ A = α = 14.43773009655° = 14°26'14″ = 0.25219784369 rad
Angle ∠ B = β = 71.33770751151° = 71°20'13″ = 1.24550668395 rad
Angle ∠ C = γ = 94.22656239195° = 94°13'32″ = 1.64545473771 rad

Height: ha = 18.94883508517
Height: hb = 4.98664081189
Height: hc = 4.73770877129

Median: ma = 19.34655421222
Median: mb = 11.05766721937
Median: mc = 9.6443650761

Inradius: r = 2.15332216877
Circumradius: R = 10.02772578594

Vertex coordinates: A[20; 0] B[0; 0] C[1.6; 4.73770877129]
Centroid: CG[7.2; 1.57990292376]
Coordinates of the circumscribed circle: U[10; -0.73988505791]
Coordinates of the inscribed circle: I[3; 2.15332216877]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 165.5632699035° = 165°33'46″ = 0.25219784369 rad
∠ B' = β' = 108.6632924885° = 108°39'47″ = 1.24550668395 rad
∠ C' = γ' = 85.77443760805° = 85°46'28″ = 1.64545473771 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.