theorem Th66: :: MATRIX15:66
for K being Field
for A being Matrix of K
for N being finite without_zero Subset of NAT st N c= dom A & not N is empty & width A > 0 & ( for i being Nat st i in (dom A) \ N holds
Line (A,i) = (width A) |-> (0. K) ) holds
Space_of_Solutions_of A = Space_of_Solutions_of (Segm (A,N,(Seg (width A))))