if a = -4 and b = 3, then

(b - a)/(a - b) = (3 - (-4))/(-4 - 3) = 7/-7 = 1

but it was totally unnecessary to know the values of a and b here, as long as the value of a - b not= 0, we would get -1 as the answer (do you see why?)

if a = -2 and b = -4, thena= -2 and b= -4

b^2/a

b^2/a = (-4)^2 / -2 = 16/-2 = -8