\left[
\begin{array}{cc}
1 & y_1 \\
1 & y_2
\end{array}
\right]
\left[
\begin{array}{c}
C(z) \\ A(z)
\end{array}
\right]
=\left[
\begin{array}{c}
k_1z+n_1 \\ k_2z+n_2
\end{array}
\right],\quad
\left[
\begin{array}{ccc}
1 & y_1 & y_1^2 \\
1 & y_2 & y_2^2 \\
1 & y_3 & y_3^2
\end{array}
\right]
\left[
\begin{array}{c}
E(z) \\
D(z) \\
B(z)
\end{array}
\right]
=\left[
\begin{array}{c}
a_1z^2+b_1z+c_1 \\
a_2z^2+b_2z+c_2 \\
a_3z^2+b_3z+c_3
\end{array}
\right],