Question

If a point $P(x, y, z)$ lies on the XZ- plane, then which of the following must be true?

• A. $x=0$
• B. $y=0$

Answer 1

Answer: (B)

$y=0$

Answer 2

For a point $P(x, y, z)$ to lie on the XZ-plane, its perpendicular distance from the XZ-plane must be zero. The y-coordinate represents this perpendicular distance. Hence, $y=0$.