\(=\dfrac{5\cdot6^{18}\cdot2^{12}-2\cdot2^{28}\cdot3^{14}\cdot3^4}{5\cdot2^{28}\cdot3^{18}-7\cdot2^{29}\cdot3^{18}}\)
\(=\dfrac{5\cdot2^{30}\cdot3^{18}-2^{29}\cdot3^{18}}{5\cdot2^{28}\cdot3^{18}-7\cdot2^{29}\cdot3^{18}}\)
\(=\dfrac{3^{18}\cdot2^{29}\left(5\cdot2-1\right)}{2^{28}\cdot3^{18}\left(5-7\cdot2\right)}=\dfrac{2\cdot9}{-9}=-2\)