Look at the previous formula, if
So a is greater than 0.
So the solution set of x=b/a is (1, +∞)= & gt;; a=b
∵(ax+b)/(x+2)>0 So (ax+b) * (x+2) > 0
So a(x+ 1)*(x+2)>0.
The solution set is (-∞, -2)∩(- 1,+∞).