Question

which of the following equations represents a line perpendicular to y=0?

○ y=x

○ y=-x

○ x=3

○ y=3

Explanation:

Step1: Identify line $y=0$

$y=0$ is a horizontal x-axis line, slope $m_1=0$.

Step2: Find perpendicular slope

Perpendicular lines have slopes that are negative reciprocals; a line perpendicular to horizontal is vertical, with undefined slope.

Step3: Match vertical line form

Vertical lines have the form $x=k$ (constant $k$).

Step4: Select correct option

Among choices, $x=3$ is vertical.

Answer:

C. $x=3$