# 11 11 19 triangle

### Obtuse isosceles triangle.

Sides: a = 11   b = 11   c = 19

Area: T = 52.68800484054
Perimeter: p = 41
Semiperimeter: s = 20.5

Angle ∠ A = α = 30.27326413189° = 30°16'22″ = 0.52883572643 rad
Angle ∠ B = β = 30.27326413189° = 30°16'22″ = 0.52883572643 rad
Angle ∠ C = γ = 119.4554717362° = 119°27'17″ = 2.0854878125 rad

Height: ha = 9.57881906192
Height: hb = 9.57881906192
Height: hc = 5.54552682532

Median: ma = 14.5177231141
Median: mb = 14.5177231141
Median: mc = 5.54552682532

Inradius: r = 2.57697584588
Circumradius: R = 10.91102025795

Vertex coordinates: A[19; 0] B[0; 0] C[9.5; 5.54552682532]
Centroid: CG[9.5; 1.84884227511]
Coordinates of the circumscribed circle: U[9.5; -5.36549343263]
Coordinates of the inscribed circle: I[9.5; 2.57697584588]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 149.7277358681° = 149°43'38″ = 0.52883572643 rad
∠ B' = β' = 149.7277358681° = 149°43'38″ = 0.52883572643 rad
∠ C' = γ' = 60.54552826378° = 60°32'43″ = 2.0854878125 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.