(10ac-x)/11=-3 solve for a
\(\frac{(10ac-x)}{11}=-3 \\\\ 10ac-x=-33 \\\\ 10ac=-33+x \\\\ \boxed{a=\frac{x-33}{10c}}\)
\(\frac{(10ac-x)}{11}=-3\ \ \ \ | multiply\ by\ 11\\\\ 10ac-x=-33\ \ \ \ | add\ x\\\\ 10ac=-33+x\ \ \ \ | divide\ by\ 10c\\\\ \boxed{a=\frac{-33+x}{10c}}\)
