\(A=\frac{4^6x9^5+6^9x120}{8^4x3^{12}-6^{11}}\)
\(A=\frac{2^{12}x3^{10}+2^9x3^9x2^3x3x5}{2^{12}x3^{12}-2^{11}x3^{11}}\)
\(A=\frac{2^{12}.3^{10}+2^{12}.3^{10}.5}{2^{12}.3^{10}-2^{11}.3^{11}}\)
\(A=\frac{2^{12}.3^{10}.\left(1+5\right)}{2^{11}.3^{10}.\left(2-3\right)}=\frac{2.6}{-1}=-12\)