The linear system is
Draw a coordinate plane
\Draw the linear equation
Draw the linear equation 
Plot the intersection point 
.bmp\")
Check:
\To check solution, substitute x for 1 and y for -1 in the linear equations.
\
(Substitute x for 1 and y for
)
(Simplify)

(Substitute x for 1 and y for
)
(Simplify)
The point satisfies the linear system. so, the solution is
.
The solution is
.