2. Walking the planck (not having minimum distances to the reference point)
\begin{align} ΣM_S=0 =&\cssId{Step1}{M_A - M_{mg} - M_{mpg}}\\[3px] &\cssId{Step2}{F_A * x_{min1} - mg * x_{min2} - m_pg * x_{min3} =0}\\[3px] &\cssId{Step3}{ F_A = \frac{mg * x_{min2} + m_pg * x_{min3}}{x_min1}}\\[3px] &\cssId{Step4}{ F_A = \frac{mg * x_2 * cos(α) + m_pg * x_3 * cos(α)}{x_1 * cos(α)}}\\[3px] \end{align}