Answer
$x+y+z=1$
Work Step by Step
The standard equation of a plane passing through the point $(x_1,y_1,z_1)$ can be defined as:
$a(x-x_1)+b(y-y_1)+c(z-z_1)=0$
The normal vector to the plane is given by: $n=\lt 1,1,1 \gt$
$1(x -1)+1(y -0)+1(z-0)=0 \implies x-1+y+z=0$
