`(x^3 - 7x^2 + x - 7) = (x-7)m`

`(x^3 - 7x^2 + x - 7) : (x - 7) = m`

`[x^2(x - 7) + (x - 7)] : (x - 7) = m`

`(x - 7)(x^2 + 1) : (x - 7) = m`

`m = x^2 + 1`