As vehicular networking advances, increasing interactions between vehicles and cloudlets have heightened the demand for computing resources. Mobile edge computing (MEC) addresses this challenge by utilizing edge resources to meet growing computational needs. This study introduces a communication scenario within vehicular networks, featuring an MEC-enabled roadside unit in interaction with multiple vehicles. We introduce an innovative approach that concurrently optimizes the allocation of power and bandwidth, to minimize overall energy consumption. The complexity of the original problem, attributed to the interplay of numerous optimization variables, is effectively managed by directly applying the Lagrange multiplier method to address the optimization challenges. Simulations demonstrate the proposed method achieves a substantial reduction in energy consumption, significantly outperforming existing benchmarks and highlighting its effectiveness.