# 3 19 19 triangle

### Acute isosceles triangle.

Sides: a = 3   b = 19   c = 19

Area: T = 28.41110453873
Perimeter: p = 41
Semiperimeter: s = 20.5

Angle ∠ A = α = 9.05661260276° = 9°3'22″ = 0.15880592167 rad
Angle ∠ B = β = 85.47219369862° = 85°28'19″ = 1.49217667185 rad
Angle ∠ C = γ = 85.47219369862° = 85°28'19″ = 1.49217667185 rad

Height: ha = 18.94106969249
Height: hb = 2.99106363566
Height: hc = 2.99106363566

Median: ma = 18.94106969249
Median: mb = 9.7343961167
Median: mc = 9.7343961167

Inradius: r = 1.3865904653
Circumradius: R = 9.53297443761

Vertex coordinates: A[19; 0] B[0; 0] C[0.23768421053; 2.99106363566]
Centroid: CG[6.41222807018; 0.99768787855]
Coordinates of the circumscribed circle: U[9.5; 0.75223482402]
Coordinates of the inscribed circle: I[1.5; 1.3865904653]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 170.9443873972° = 170°56'38″ = 0.15880592167 rad
∠ B' = β' = 94.52880630138° = 94°31'41″ = 1.49217667185 rad
∠ C' = γ' = 94.52880630138° = 94°31'41″ = 1.49217667185 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.