How can I pass a variable and a string into the same jQuery selector?

I have the following:

var x = '.'+this.id;  

and this does not work:

$(x,'#thumb').show();

but this does:

$(x).show();

and obviously so does this:

$('#thumb').show();

What am I missing? Should I be doing something else in gener开发者_如何学Pythonal to pass variables (even on their own) through jQuery?

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You need to concatenate the two strings together:

$(x+',#thumb').show();