Final answer:
The equation that best represents the line in the graph is y = 3x + 9.
Step-by-step explanation:
The equation that best represents the line in the graph is y = mx + b, where m is the slope of the line and b is the y-intercept. The slope of a line represents the change in y-values for every one unit change in x-values, while the y-intercept is the point where the line intersects the y-axis.
In the given graph, the line has a slope of 3 and a y-intercept of 9. So, the equation that represents the line is y = 3x + 9.