theorem Th63:

for

A,

B,

C being

Point of

(TOP-REAL 2) st

A,

B,

C is_a_triangle holds

ex

D being

Point of

(TOP-REAL 2) st

(

(median (A,B,C)) /\ (median (B,C,A)) = {D} &

(median (B,C,A)) /\ (median (C,A,B)) = {D} &

(median (C,A,B)) /\ (median (A,B,C)) = {D} )