`text{Ta có}`
`+) log_{3} a + log_{9} (b^{4}) - 13 = 0`
`-> log_{3} a + 4log_{3^{2}} b = 13`
`-> log_{3} a + 2log_{3} b = 13` `(1)`
`+) log_{9) a^{10} + log_{3} b^3 - 30 = 0`
`-> 10log_{3^{2}} a + 3log_{3} b = 30`
`-> 5log_{3} a + 3log_{3} b = 30` `(2)`
`text{Từ (1)(2)}`
`->` \(\left\{ \begin{array}{l}log_{3} a + 2log_{3} b = 13\\5log_{3} a + 3log_{3} b = 30\end{array} \right.\)
`->` \(\left\{ \begin{array}{l}log_{3} a = 3\\log_{3} b = 5\end{array} \right.\)
`->` \(\left\{ \begin{array}{l}a = 3^{3} = 27\\b = 3^{5} = 243\end{array} \right.\)
`-> S = 27 + 243 = 270`
`-> text{Chọn B}`
