ai giúp e gấp câu b vs ạ =___))

`b)` `3\sqrt{9x-9} - \sqrt{4x-4} = \sqrt{x-1} + 24` `( ĐK : x >= 1 )`

`<=> 3\sqrt{9 ( x - 1 )} - \sqrt{4 ( x - 1 )} - \sqrt{x-1} - 24 = 0`

`<=> 3 . 3\sqrt{x-1} - 2\sqrt{x-1} - \sqrt{x-1} = 24`

`<=> 9\sqrt{x-1} - 2\sqrt{x-1} - \sqrt{x-1} = 24`

`<=> ( 9 - 2 - 1 )\sqrt{x-1} = 24`

`<=> 6\sqrt{x-1} = 24`

`<=> \sqrt{x-1} = 4`

`<=> x - 1 = 16`

`<=> x = 17 ( tm )`

Vậy `S = { 17 }`