Solve $x\equiv 2\pmod 5, x\equiv 1\pmod 8, x\equiv 7\pmod 9, x\equiv -3\pmod {11}$ for $x\in\mathbb Z$.
$x\equiv a_i\pmod {m_i}$
The system of congruences has a unique solution modulo M($m_1, m_2, m_3, m_4$)
$x:= a_1\frac{M}{m_1}b_1+a_2\frac{M}{m_2}b_2+a_3\frac{M}{m_3}b_3+a_4\frac{M}{m_4}b_4$
$x:= 2\frac{M}{5}b_1+\frac{M}{8}b_2+7\frac{M}{9}b_3-3\frac{M}{11}b_4$
$M=3960$
$x:= 1584b_1+495b_2+3080b_3-1080b_4$
I am not sure what i should do next to solve for $b_i$...