Question

Helpppp

Answer 1

Đk: `x >=2`.

`sqrt(x-2) =x-4`

`x-2 = x^2 - 8x + 16`

`x^2 - 9x + 18 = 0`

`\Delta = 81 - 18 xx 4 = 9`.

`=> x = (9+3)/2 = 6` hoặc `x =(9-3)/2 = 3`.