Answer
The set of points of the form $(x, 3)$ is a horizontal line, $3$ units above $x$-axis.
Refer to the plot below.
Work Step by Step
To locate the point $(0, 3)$, from the origin, go $3$ units straight above $0$ and place a dot at this location.
To locate the point $(1, 3)$, from the origin, go $1$ unit to the right of $0$ along the $x$-axis and go $3$ units straight up. We plot the point by placing a dot at this location.
To locate the point $(−2, 3)$, from the origin, go $2$ units to the left of $0$ along the $x$-axis and go $3$ units straight up. We plot the point by placing a dot at this location.
To locate the point $(5, 3)$, from the origin, go $5$ units to the right of $0$ along the $x$-axis and go $3$ units straight up. We plot the point by placing a dot at this location.
To locate the point $(−4, 3)$, from the origin, go $4$ units to the left of $0$ along the $x$-axis and go $3$ units straight up. We plot the point by placing a dot at this location.
The points are on a horizontal line, 3 units above x-axis.