Given that $V$ is an invertible $n\times n$ matrix and $\Sigma$ is a diagonal rectangular $m\times n$ matrix, $U$ is an $m\times m$ matrix, $b$ is an $m\times 1$ matrix and $\lambda$ is a positive number, how do you further simplify the given equation
$$x = (V^T)^{-1}(\Sigma^T\Sigma+\lambda I)^{-1}\Sigma^TU^Tb$$