Step 1: Concept/Formula
The equation of a line formula in slope-intercept form can be written as shown below.

Where, m = slope and c is the intercept on the y-axis
Step 2:
Since the line is horizontal, the line will pass through the intercept at 6.
Graph
Step 3: Find the slope m and intercept c.
From the graph, Slope m = 0 because the line is horizontal.
The intercept c = 6
Step 4: Equation of a line.
The equation of a line in slope-intercept form is given as:

The equation of line is: y = 6