Question

The distance of point $P(3,4,5)$ from the $yz$-plane is

• A. $3$ units
• B. $4$ units
• C. $5$ units
• D. $550$ units

Answer 1

Answer: (A)

When we draw a perpendicular line from $P(3,4,5)$ on the $yz$-plane, the $x$-coordinate will be zero, and they and $z$-coordinates be $4$ and $5$ respectively.
$\therefore$ Coordinate of a point on $yz$-plane be $Q\left(0,4,5\right)$
$\therefore PQ=\sqrt{{\left(3-0\right)}^2+{\left(4-4\right)}^2+{\left(5-5\right)}^2}=3$ units