Answer:
m = -1/4
Explanation:
4y + x = 8
Arrange the equation in a slope intercept form y = mx+b, where m is the slope
4y + x = 8, subtract x from both sides
 4y = -x +8, divide both sides by 4
 y = -x/4 + 8/4 , simplify
 y = -x/4 + 2, compare this to the general form y=mx+b and we see that the slope m = -1/4