The state space representation of a first-order system is
\[
\dot{X} = -X + U, Y = X
\]
where \(X\) is the state variable, \(u\) is the control input and \(y\) is the controlled output. Let \(u = -KX\) be the control law. To place a closed-loop pole at \(-2\), the value of \(K\) is \(\underline{\hspace{1cm}}\).
