Critical values ,

That isn't a solution. These are the possible "changes" - the boundaries of the inequalities. To test, choose one value on each side of every c.v.

One value greater than :

So x can be greater than as this fits the inequality.

One value within the range , such as

So values within the range do not suit the inequality.

One value less than , such as

So values less than -5 work, and values greater than 1 work, as these are the only values which suit the inequality.

Can you do the same for the second inequality? Then you just need to find the values which are within the accepted range for both. Post your working if you get stuck.