The equation of a horizontal line can be written in the form y = c, where c is a constant representing the y-value for all points on the line.
In this case, the point given is (2, 4). This means that for every point on this line, the y-coordinate remains constant at 4, regardless of the x-coordinate. Therefore, the equation of the horizontal line passing through the point (2, 4) is:
y = 4
This line will run parallel to the x-axis and pass through (2, 4) as well as all other points where the y-coordinate is 4, such as (1, 4), (3, 4), and (100, 4).