solve; 10ac-x/11=-3, for a
\(\dfrac{10ac-x}{11}=-3\ \ \ \ |multiply\ both\ sides\ by\ 11\\\\10ac-x=-33\ \ \ |add\ x\ to\ both\ sides\\\\10ac=x-33\ \ \ |divide\ both\ sides\ by\ 10c\\\\\boxed{a=\frac{x-33}{10c}}\)
