[tex]\bf \begin{array}{|rrrr|ll} \cline{1-4} \stackrel{domain}{x}&\stackrel{f(x)}{-x+4}&&range\\ \cline{1-4} -3&-(-3)+4\to &3+4\to &7\\ -2&-(-2)+4\to &2+4\to &6\\ -1&-(-1)+4\to &1+4\to &5\\ 1&-(1)+4\to &-1+4\to &3\\ \cline{1-4} \end{array}\qquad\qquad \stackrel{\mathbb{RANGE}}{\{7,6,5,3\}}[/tex]