How do I echo a sum of a variable and a number?

Question

I have a variable x=7 and I want to echo it plus one, like echo ($x+1) but I\'m getting:

bash: syntax error near unexpected

Answer 1

try echo $(($x + 1))

I think that only works on some version of bash that is 3 or more..

echo `expr $x + 1`

would be another solution