Mathematics - 3D Coordinate Geometry Question with Solution | TestHub

The required plane passes through the point $(7,8,6)$ and is parallel to XY plane. $\therefore$ It is perpendicular to $\mathrm{z}$ axis and direction ratios of $\mathrm{z}$ axis are $0,0,1$. $\therefore$ Required equation of plane is $$0(\mathrm{x}-7)+0(\mathrm{y}-8)+1(\mathrm{z}-6)=0\Rightarrow \mathrm{z}=6$$