I- please ask a question. This is not a question
Answer:
I think its. u must check with calculator
The given plane,
, has normal vector
. Any plane parallel to this one has the same normal vector.
Let
be any point in the plane we want. The plane contains the point (1, 1, -1), so an arbitrary vector in this plane is

and this is perpendicular to
.
So the equation of the plane is

or equivalently,
