Quick less than an hour whats the answer for this?

Question

Let A be a 3x3 matrix, and suppose that the matrix B is obtained from A by : R₁←→R₂; 5R₂+R₃→R₃.

If |A|= -12, then |B| =??

Answer 1

Determinants |B| = |A| = - 12. This follows from properties of determinants