$$ \begin{cases} m_A&=46.0\ut{kg}\\L&=5.00\ut{m}\\m_B&=250\ut{kg}\\d&=0.540\ut{m}\\\end{cases} $$$$ \begin{cases} x_1&=d\\x_2&=L-d\\x_A&=L\\x_B&={L\over2}\\\end{cases} $$$$ \begin{cases} \Sigma F_{y}&=0\\\Sigma \tau&=0\\\end{cases} $$$$ \begin{cases} 0&=N_1+N_2-m_Ag-m_Bg\\0&=x_1N_1+x_2N_2-x_Am_Ag-x_Bm_Bg\\\end{cases} $$$$\ab{a,b}$$$$ \begin{cases} N_1&=\cfrac{ m_A (x_A-x_2)+m_B (x_B-x_2)}{x_1-..