vecterd (l,l.3) .c2.3.6] a (libis) form Do the budia fer R?

Assume that A is row equivalent to B. Find bases for Nul A, Col A, and Row A. 11 5 3 6 11 0 2 5 11 2 6 0 0 5 -5 5 A = B = 4 4 - 5 13 9 0 0 0 - 4 2 2 4 9 0 0 0 A column vector basis for Nul A is (Use a comma to separate vectors as needed.) A column vector basis for Col A is }. (Use a comma to separate vectors as needed.) A row vector basis for Row A is } (Use a comma to separate vectors as needed.)

Is it true that when an n*n matrix whose columns form a basis of R^n, then A is invertible?

How is the basis {lk} picked?