# 20 23 23 triangle

### Acute isosceles triangle.

Sides: a = 20   b = 23   c = 23

Area: T = 207.1233151772
Perimeter: p = 66
Semiperimeter: s = 33

Angle ∠ A = α = 51.54329234811° = 51°32'35″ = 0.98995937208 rad
Angle ∠ B = β = 64.22985382594° = 64°13'43″ = 1.12109994664 rad
Angle ∠ C = γ = 64.22985382594° = 64°13'43″ = 1.12109994664 rad

Height: ha = 20.71223151772
Height: hb = 18.01107088497
Height: hc = 18.01107088497

Median: ma = 20.71223151772
Median: mb = 18.22877261336
Median: mc = 18.22877261336

Inradius: r = 6.27664591446
Circumradius: R = 12.77701803365

Vertex coordinates: A[23; 0] B[0; 0] C[8.69656521739; 18.01107088497]
Centroid: CG[10.56552173913; 6.00435696166]
Coordinates of the circumscribed circle: U[11.5; 5.55222523202]
Coordinates of the inscribed circle: I[10; 6.27664591446]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 128.4577076519° = 128°27'25″ = 0.98995937208 rad
∠ B' = β' = 115.7711461741° = 115°46'17″ = 1.12109994664 rad
∠ C' = γ' = 115.7711461741° = 115°46'17″ = 1.12109994664 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.