$11 \times (x -6 ) = 4 \times x + 11$
$11 \times x - 11 \times 6 = 4 \times x +11$
$11 \times x - 66 = 4 \times x + 11$
$11 \times x = 4 \times x + 11+ 66$
$11 \times x = 4 \times x + 77$
$11 \times x - 4 \times x = 77$
$7 \times x = 77$
$ x = 77:7$
$ x = 11$
Vậy $x=11$