For example: (x-2)(x+3)>0, it can be solved as (x-2)(x+3)=0, and x=2 or x=-3 can be calculated. Look at the symbol at this time (this question is greater than the symbol), and then take the solution on both sides, that is, X.
On the contrary, if it is less than the number (x-2) (x+3)
In short, this is a rule. When the unknown coefficient is greater than 0, the greater than sign takes both sides and the less than sign takes the middle.
You can ask if you don't understand. If you are satisfied, please adopt ~ _