Find the slope of the following linear equation. If the slope is undefined, enter UND for "undefined". \[ x=9 \] Answer 2 Points < \( \mathrm{x}=\mathrm{m} \)

The equation \( x = 9 \) represents a vertical line on the Cartesian plane. Vertical lines have an undefined slope because they do not rise or fall as they run parallel to the y-axis. The classic way of thinking about slope, which is the rise over run, doesn't apply here since there's no horizontal movement; hence, attempting to divide by zero leads to that infamous undefined status! Just like a road that goes straight up or down with no room for left or right turns, a vertical line's direction is fixed. So when you see \( x = 9 \), remember, it’s not just a number—it’s a marker indicating an infinite rise without any run!