x does not mean do not play. It means play muted.
For the first pattern you posted, it must be played like this. Touch the 4 strings with one finger (like a barre) but do not press all the way down; position doesn't matter but it's better if you do this near the fret where you are playing the next chord so that you don't have to move your hand too much. Now if you strike the strings you will get a 'click' sound. That's the effect you need to achieve.
The second one is similar, but on a single string. Mute the string to get the click sound then fret the next note open (0) as indicated. So you should get a 'click' and then the open string sound.
Since the creation of the Internet, the Earth's rotation has been fueled, primarily, by the collective spinning of English teachers in their graves. (QDB #754533)