\[\boxed{\mathbf{846}.}\]
\[1)\log_{5}x^{2} = 0\ \]
\[x^{2} = 5^{0}\]
\[x^{2} = 1\]
\[x = \pm 1.\]
\[Ответ:x = \pm 1.\]
\[2)\log_{4}x^{2} = 3\ \]
\[x^{2} = 4^{3}\]
\[x^{2} = 64\]
\[x = \pm 8.\]
\[Ответ:x = \pm 8.\]
\[3)\log_{3}x^{3} = 0\]
\[x^{3} = 3^{0}\]
\[x^{3} = 1\]
\[x = 1.\]
\[Ответ:x = 1.\]
\[4)\log_{4}x^{3} = 6\]
\[x^{3} = 4^{6}\]
\[x^{3} = \left( 4^{2} \right)^{3}\]
\[x = 16.\]
\[Ответ:x = 16.\]
\[5)\lg x^{4} + \lg{4x} = 2 + \lg x^{3}\]
\[4\lg x + \lg 4 + \lg x = 2 + 3\lg x\]
\[2\lg x = 2 - \lg 4\]
\[2\lg x = 2 - \lg 2^{2}\]
\[2\lg x = 2 - 2\lg 2\ \ \ \ \ \ \ \ \ |\ :2\]
\[\lg x = 1 - \lg 2\]
\[x = 10^{1 - \lg 2}\]
\[x = \frac{10^{1}}{10^{\lg 2}} = \frac{10}{2} = 5.\]
\[Ответ:x = 5.\]
\[6)\lg x + \lg x^{2} = \lg{9x}\ \]
\[\lg x + 2\lg x = \lg 9 + \lg x\]
\[2\lg x = \lg 3^{2}\]
\[2\lg x = 2\lg 3\]
\[\lg x = \lg 3\]
\[x = 3\]
\[Ответ:x = 3.\]