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\lhead{{\bfseries CSC\,320\,H1S}}
\chead{{\bfseries\large Assignment \#\,4
    --- General Instructions}}
\rhead{{\bfseries Winter 2015}}
\lfoot{{Dept. of Computer Science, University of Toronto}}
\cfoot{{}}
\rfoot{{Page \thepage\ of \pageref{LastPage}}}


\begin{document}


\chead{Matting Equation in Matrix From}

$$
\left(\begin{matrix}
1 & 	0 & 	0 & -B^{r}_1 \\
0 & 	1 & 	0 & -B^{g}_1 \\
0 & 	0 & 	1 & -B^{b}_1 \\
1 & 	0 & 	0 & -B^{r}_2 \\
0 & 	1 & 	0 & -B^{g}_2 \\
0 & 	0 & 	1 & -B^{b}_2 \\
\end{matrix} \right) 
\left(\begin{matrix}
F_r \\
F_g \\
F_b \\
\alpha
\end{matrix}\right) = 
\left(
\begin{matrix}
  C^{r}_1  -B^{r}_1 \\
  C^{g}_1 -B^{g}_1 \\
  C^{b}_1 -B^{b}_1 \\
  C^{r}_2 -B^{r}_2 \\
  C^{g}_2-B^{g}_2 \\
  C^{b}_2-B^{b}_2 \\
\end{matrix}
\right).
$$


\end{document}