UsoDeMonge::usage="Obtain the Monge point for the next tetrahedron:​​
9
2
​,
3
2
​, 0​, 2,
7
2
​, 0​, ​
7
2
​, 3, 0 y ​
5
2
​,
5
2
​, 2 , then trace the crcumscribed sphere.The Monge point of a tetrahedron is the point of concurrence of the anti-mediator planes that pass through the midpoint of each edge and is perpendicular to the opposite edge.​Referencia: Wolfram MathWorld: Monge Point; Personal."
Development:
In[]:=
ρ=ResourceFunction["Monge"]
9
2
,
3
2
,0,2,
7
2
,0,
7
2
,3,0,
5
2
,
5
2
,2
Out[]=

30
7
,
61
14
,
55
56
,Hyperplane
5
2
,-2,0,3,
11
4
,1,Hyperplane1,-
3
2
,0,
9
4
,3,1,Hyperplane{2,-1,-2},
11
4
,
13
4
,0,Hyperplane-
3
2
,
1
2
,0,
7
2
,2,1,Hyperplane-
1
2
,1,-2,4,
9
4
,0,Hyperplane1,
1
2
,-2,
13
4
,
5
2
,0
tet=
9
2
,
3
2
,0,2,
7
2
,0,
7
2
,3,0,
5
2
,
5
2
,2;​​Graphics3D[{Tube[#]&/@Subsets[tet,{2}],Green,Sphere[ρ[[1]],0.05],Opacity[.4],Red,Polygon/@Subsets[tet,{3}],Yellow,Opacity[.2],ρ[[2]]}]
Out[]=
Barycenter coordinates:
In[]:=
G=

9
2
,
3
2
,0+2,
7
2
,0+
7
2
,3,0+
5
2
,
5
2
,2
4
Out[]=

25
8
,
21
8
,
1
2

Obtaining the coordinates of the circumcenter::
Knowing that the barycenter is the midpoint of the segment whose ends are the circumcenter and the point of Monge, we have::
Circumcenter=2G-M;​​Circumcenter=2
25
8
,
21
8
,
1
2
-
30
7
,
61
14
,
55
56
​​
Out[]=

55
28
,
25
28
,
1
56

Radius of the sphere:
In[]:=
r=Norm
55
28
,
25
28
,
1
56
-
9
2
,
3
2
,0
Out[]=
3
2369
56
In[]:=
r=Norm
55
28
,
25
28
,
1
56
-2,
7
2
,0
Out[]=
3
2369
56
In[]:=
r=Norm
55
28
,
25
28
,
1
56
-
7
2
,3,0
Out[]=
3
2369
56
In[]:=
r=Norm
55
28
,
25
28
,
1
56
-
5
2
,
5
2
,2
Out[]=
3
2369
56
What we wanted to show..
Full graph:
In[]:=
Showρ=ResourceFunction["Monge"]
9
2
,
3
2
,0,2,
7
2
,0,
7
2
,3,0,
5
2
,
5
2
,2;​​tet=
9
2
,
3
2
,0,2,
7
2
,0,
7
2
,3,0,
5
2
,
5
2
,2;​​Graphics3D[{Tube[#]&/@Subsets[tet,{2}],Green,Sphere[ρ[[1]],0.08],Opacity[.4],Red,Polygon/@Subsets[tet,{3}],Yellow,Opacity[.2],ρ[[2]]}],Graphics3DBlue,Opacity[0.2],Sphere
55
28
,
25
28
,
1
56
,
3
2369
56
,Graphics3DBlack,Ball
55
28
,
25
28
,
1
56
,0.08,Graphics3DBlack,Ball
25
8
,
21
8
,
1
2
,0.08
Out[]=