# 9 19 19 triangle

### Acute isosceles triangle.

Sides: a = 9   b = 19   c = 19

Area: T = 83.06773672389
Perimeter: p = 47
Semiperimeter: s = 23.5

Angle ∠ A = α = 27.44004669767° = 27°24'2″ = 0.47882283653 rad
Angle ∠ B = β = 76.32997665116° = 76°17'59″ = 1.33216821441 rad
Angle ∠ C = γ = 76.32997665116° = 76°17'59″ = 1.33216821441 rad

Height: ha = 18.4599414942
Height: hb = 8.74439333936
Height: hc = 8.74439333936

Median: ma = 18.4599414942
Median: mb = 11.4354596626
Median: mc = 11.4354596626

Inradius: r = 3.53547815846
Circumradius: R = 9.77882080617

Vertex coordinates: A[19; 0] B[0; 0] C[2.13215789474; 8.74439333936]
Centroid: CG[7.04438596491; 2.91546444645]
Coordinates of the circumscribed circle: U[9.5; 2.3165891383]
Coordinates of the inscribed circle: I[4.5; 3.53547815846]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 152.6599533023° = 152°35'58″ = 0.47882283653 rad
∠ B' = β' = 103.7700233488° = 103°42'1″ = 1.33216821441 rad
∠ C' = γ' = 103.7700233488° = 103°42'1″ = 1.33216821441 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.