# 5 18 19 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 18   c = 19

Area: T = 44.98998886413
Perimeter: p = 42
Semiperimeter: s = 21

Angle ∠ A = α = 15.22327570342° = 15°13'22″ = 0.26656872315 rad
Angle ∠ B = β = 70.95546892365° = 70°57'17″ = 1.23883929469 rad
Angle ∠ C = γ = 93.82325537293° = 93°49'21″ = 1.63875124752 rad

Height: ha = 17.96599554565
Height: hb = 4.98988765157
Height: hc = 4.72663040675

Median: ma = 18.33771208209
Median: mb = 10.58330052443
Median: mc = 9.17987798753

Inradius: r = 2.13880899353
Circumradius: R = 9.52111817431

Vertex coordinates: A[19; 0] B[0; 0] C[1.63215789474; 4.72663040675]
Centroid: CG[6.87771929825; 1.57554346892]
Coordinates of the circumscribed circle: U[9.5; -0.63547454495]
Coordinates of the inscribed circle: I[3; 2.13880899353]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 164.7777242966° = 164°46'38″ = 0.26656872315 rad
∠ B' = β' = 109.0455310763° = 109°2'43″ = 1.23883929469 rad
∠ C' = γ' = 86.17774462707° = 86°10'39″ = 1.63875124752 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.