how would you calculate the monthly payment without using a financial function?

\begin{tabular}{|l|r|} \hline Input & \\ \hline Purchase Price & $50,000.00 \\ \hline Sales Tax & 7% \\ \hline Down Payment & 10% \\ \hline Months Financed & 72 \\ \hline APR & 3.25% \\ \hline Output & \\ \hline Down Payment Amount & $5,000.00 \\ \hline Amount Financed & $45,000.00 \\ \hline Tax Owed & $3,500.00 \\ \hline Monthly Payment & \\ \hline \end{tabular}