Given the line:

You need to remember the Slope-Intercept Form of the equation of a line:

Where "m" is the slope of the line and "b" is the y-intercept.
In order to write the given equation in Slope-Intercept Form, you have to solve for "y":

Notice that:

By definition, the slopes of parallel lines are equal. Therefore, the slope of a line parallel to the given must be:

Hence, the answer is:
