Q.
If the system of linear equations.
$ 8 x+y+4 z=-2 $
$ x+y+z=0 $
$ \lambda x-3 y=\mu$
has infinitely many solutions, then the distance of the point $\left(\lambda, \mu,-\frac{1}{2}\right)$ from the plane $8 x + y +4 z +2=0$ is :
Solution: