Помогите решить плз\\

Решите задачу:

$l:\; \; \frac{x-1}{1} =\frac{y+1}{2} = \frac{z+1}{-1} \; ,\; \; M(2,0,1)\in \alpha ,\; \; l\in \alpha \\\\M_0(1,-1,-1)\in l\; ,\; \; \vec {s}=(1,2,-1)\in \alpha \\\\\overline {M_0M}=(1,1,2)\in \alpha \\\\\vec {n_{ \alpha }}= \left|\begin{array}{ccc}i&j&k\\1&2&-1\\1&1&2\end{array}\right| =i(4+1)-j(2+1)+k(1-2)=5i-3i-k\\\\ \alpha :\; \; 5(x-2)-3(y-0)-(z-1)=0\\\\ \alpha :\; \; \; \underline {5x-3y-z-9=0}$