solve the equations: -1/2 x-2=-1/2( x+4)

Solution =

Solve the system of equations by graphing: $\displaystyle {\left\lbrace\begin{array}{cc} {y}=&-\frac{{1}}{{2}}{x}-{2}\\{y}=&-\frac{{1}}{{2}}{\left({x}+{4}\right)}\end{array}\right.}$
Graph will "snap to" every 1 points

How do you know how many solutions there are?