C$\left| {\,\begin{array}{*{20}{c}}7&3&{ - 5}\\6&1&1\\1&{ - 4}&2\end{array}\,} \right| \div \left| {\,\begin{array}{*{20}{c}}2&3&{ - 5}\\1&1&1\\3&{ - 4}&2\end{array}\,} \right|$
(c) For the given set of equation, by Cramer’s Rule $x = \frac{{{D_x}}}{D} = \left| {\,\begin{array}{*{20}{c}}7&{\,\,3}&{ - 5}\\6&{\,\,1}&{\,\,1}\\1&{ - 4}&{\,\,2}\end{array}\,} \right|\, \div \left| {\,\begin{array}{*{20}{c}}2&{\,\,3}&{ - 5}\\1&{\,\,1}&{\,\,1}\\3&{ - 4}&{\,\,2}\end{array}\,} \right|$.