You have the following equation:
y = 3x
The general form of the equation of the line is:
y = mx + b
where m is the slope and b is the y-intercept. By comparing the general form of the equation of the line, with the given equation y=3x, you can notice that the slope is m = 3 and that the y-intercept is b = 0.
The following image is a graph of the equation:
