Morley's Theorem

Morley:=proc() local m,n,A,B,C,D,E,F:

C:=Pt(  (y-A[2])-TS(m,m,m)*(x-A[1])   ,   (y-B[2])+TS(n,n,n)*(x-B[1])  ):

D:=Pt(   (y-A[2])-m*(x-A[1])   ,   (y-B[2])+n*(x-B[1])   ):
E:=Pt(   (y-A[2])-TS(m,m)*(x-A[1])   ,   (y-C[2])-(x-C[1])*TS(m,m,-n,sqrt(3))   ):
F:=Pt(   (y-B[2])+TS(n,n)*(x-B[1])   ,   (y-C[2])+(x-C[1])*TS(n,n,-m,sqrt(3))   ):

ItIsEquilateral (D,E,F):

end: