For the system of linear equations $$\begin{array}{cc}x-y=7& \\ y=-x+5& \end{array}$$ which of the following moves is correct?

	(a)	$$\begin{array}{cc}-y=x+7& \\ y=-x+5& \end{array}$$			(b)	$$\begin{array}{cc}-y=-x+7& \\ y=-x+5& \end{array}$$
	(c)	$$\begin{array}{cc}y=x+7& \\ y=-x+5& \end{array}$$			(d)	$$\begin{array}{cc}y=-x-7& \\ y=-x+5& \end{array}$$

For the system of linear equations $$\begin{array}{cc}-y=-x+7& \\ y=-x+5& \end{array}$$ which of the following moves is correct?

	(a)	$$\begin{array}{cc}y=-x+7& \\ y=-x+5& \end{array}$$			(b)	$$\begin{array}{cc}-y=x+7& \\ y=-x+5& \end{array}$$
	(c)	$$\begin{array}{cc}y=x-7& \\ y=-x+5& \end{array}$$			(d)	$$\begin{array}{cc}-y=-x-7& \\ y=-x+5& \end{array}$$

For the system of linear equations $$\begin{array}{cc}y=x-7& \\ y=-x+5& \end{array}$$ which of the following moves is correct?

	(a)	$$\begin{array}{cc}x-7=x+5& \end{array}$$			(b)	$$\begin{array}{cc}x-7=-x+5& \end{array}$$
	(c)	$$\begin{array}{cc}x+7=x+5& \end{array}$$			(d)	$$\begin{array}{cc}x-7=x-5& \end{array}$$

For the linear equation $$\begin{array}{cc}x-7=-x+5& \end{array}$$ which of the following moves is correct?

	(a)	$$\begin{array}{cc}2x-7=5& \end{array}$$			(b)	$$\begin{array}{cc}-7=5& \end{array}$$
	(c)	$$\begin{array}{cc}-7=2x+5& \end{array}$$			(d)	$$\begin{array}{cc}2x+7=5& \end{array}$$
	(e)	$$\begin{array}{cc}-2x+7=5& \end{array}$$			(f)	$$\begin{array}{cc}-2x-7=5& \end{array}$$

For the linear equation $$\begin{array}{cc}-x-7=-x+5& \end{array}$$ which of the following moves is correct?

	(a)	$$\begin{array}{cc}-x-7=-x+5& \end{array}$$			(b)	$$\begin{array}{cc}-y=x+7& \\ y=-x+5& \end{array}$$
	(c)	$$\begin{array}{cc}y=x+7& \\ y=-x+5& \end{array}$$			(d)	$$\begin{array}{cc}y=-x-7& \\ y=-x+5& \end{array}$$