1. The problem is to simplify the expression $2x$. 2. The expression $2x$ means $2$ times $x$, where $x$ is a variable. 3. Since there is no further operation or value given for $x$, the expression $2x$ is already in its simplest form. 4. Therefore, the simplified expression is $2x$. This is a basic algebraic expression representing a variable multiplied by a constant.