Point-plane distance

In Euclidean space, the point on a plane ${\displaystyle ax+by+cz=d}$ that is closest to the origin has the Cartesian coordinates ${\displaystyle (x,y,z)}$, where

The distance between the origin and point ${\displaystyle (x,y,z)}$ is ${\displaystyle {\sqrt {x^{2}+y^{2}+z^{2}}}}$.

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