theorem Th91: :: MATRIX13:91

for i, m9, n9 being Nat
for K being Field
for M9 being Matrix of n9,m9,K
for p being FinSequence of K st len p = width M9 holds
the_rank_of (DelLine (M9,i)) = the_rank_of (RLine (M9,i,((0. K) * p)))