1.
The value of kRk \in \mathbb{R}, for which the following system of linear equations
3xy+4z=3,3x - y + 4z = 3,

x+2y3z=2,x + 2y - 3z = -2,

6x+5y+kz=36x + 5y + kz = -3

has infinitely many solutions, is: