# 13 13 22 triangle

### Obtuse isosceles triangle.

Sides: a = 13   b = 13   c = 22

Area: T = 76.2110235533
Perimeter: p = 48
Semiperimeter: s = 24

Angle ∠ A = α = 32.2044227504° = 32°12'15″ = 0.5622069803 rad
Angle ∠ B = β = 32.2044227504° = 32°12'15″ = 0.5622069803 rad
Angle ∠ C = γ = 115.5921544992° = 115°35'30″ = 2.01774530476 rad

Height: ha = 11.72546516205
Height: hb = 11.72546516205
Height: hc = 6.92882032303

Median: ma = 16.86597153001
Median: mb = 16.86597153001
Median: mc = 6.92882032303

Inradius: r = 3.17554264805
Circumradius: R = 12.19765244366

Vertex coordinates: A[22; 0] B[0; 0] C[11; 6.92882032303]
Centroid: CG[11; 2.30994010768]
Coordinates of the circumscribed circle: U[11; -5.26883212064]
Coordinates of the inscribed circle: I[11; 3.17554264805]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 147.7965772496° = 147°47'45″ = 0.5622069803 rad
∠ B' = β' = 147.7965772496° = 147°47'45″ = 0.5622069803 rad
∠ C' = γ' = 64.40884550079° = 64°24'30″ = 2.01774530476 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.