Solution: There should be four situations:
① when a >; 0, both sides of the inequality are divided by a at the same time, so x
② when a
③ when A=0 and b >; 0, the solution set of the original inequality is all real numbers;
④ When A=0 and B≤0, the solution set of the original inequality is empty.
Topic: solving equations; |Ax+B|=C
(1) When c < 0, the equation has no solution;
2 when C & gt=0, ax+b = C.
X=( C-B)/A