Final answer:
The slope of a line parallel to x + y = -4 is -1.
Step-by-step explanation:
The equation of the given line is x + y = -4. To find the slope of a line parallel to this line, we need to rearrange the equation into slope-intercept form (y = mx + b), where m represents the slope. So, by subtracting x from both sides of the equation, we get y = -x - 4. The slope of this line is -1.
Since parallel lines have the same slope, any line parallel to the given line will also have a slope of -1.