0\\a^2-7a+12=0\\a_{1,2}=\frac{7^+_-1}{2}\\a_1=4\ \ \ \ \ \ \ ;a_2=3\\3^{x_1}=4\ \ \ \ \ \ ;3^{x_2}=3\\x_1=log_34\ ;x_2=1" alt="9^x-7*3^x=-12\\3^{2x}-7*3^x+12=0|3^x=a;a>0\\a^2-7a+12=0\\a_{1,2}=\frac{7^+_-1}{2}\\a_1=4\ \ \ \ \ \ \ ;a_2=3\\3^{x_1}=4\ \ \ \ \ \ ;3^{x_2}=3\\x_1=log_34\ ;x_2=1" align="absmiddle" class="latex-formula">