Answer: -1
Explanation:
To find the slope of a line parallel to the line whose equation is a + y = -4, we need to first put the equation in slope-intercept form, which is y = mx + b, where m is the slope of the line. To do this, we need to solve for y:
a + y = -4
y = -a - 4
Now we can see that the slope of the line is -1, since the coefficient of the x-term is zero. This means that any line parallel to this line will have the same slope of -1.