12-6

$${\begin{aligned} \text{Jõudude tasakaal}\\F_{\text{res},x}=0\\F_{\text{res},y}=0\\F_{\text{res},z}=0\end{aligned} \begin{aligned} \text{Jõumomentide tasakaal}\\ \tau_{\text{res},x}=0\\\tau_{\text{res},y}=0\\\tau_{\text{res},z}=0\end{aligned}}$$