Determinați [tex]x, y, z, t[/tex] dacă pe rând:

a) [tex]x\left([tex]\begin{array}{ll}2 & 5\end{array}\right)+y\left(\begin{array}{ll}4 & -3\end{array}\right)=\left(\begin{array}{ll}8 & 33\end{array}\right) ;[/tex] b) [tex]x\left(\begin{array}{l}1 \\ 2 \\ 3\end{array}\right)+y\left(\begin{array}{r}2 \\ 5 \\ -1\end{array}\right)+z\left(\begin{array}{r}4 \\ -2 \\ 3\end{array}\right)=\left(\begin{array}{r}9 \\ -3 \\ 16\end{array}\right)[/tex];

c) [tex]x\left(\begin{array}{ll}1 & 2 \\ 1 & 0\end{array}\right)+y\left(\begin{array}{ll}t & 2 \\ 3 & 0\end{array}\right)+z\left(\begin{array}{rr}0 & -1 \\ 1 & 1\end{array}\right)=\left(\begin{array}{ll}1 & 0 \\ 0 & 1\end{array}\right) ;[/tex] d) [tex]3\left(\begin{array}{ll}x & y \\ z & t\end{array}\right)=\left(\begin{array}{cc}x & 6 \\ -1 & 2 t\end{array}\right)+\left(\begin{array}{cc}4 & x+y \\ z+t & 3\end{array}\right)[/tex].[/tex]