When you created your table to see if the resulting ordered pairs matched the graph, you may not have noticed that this function contains the constant $\displaystyle-{4}\usepackage{cmbright}\Huge\$ , not 4. The graph of $\displaystyle{f{{\left({x}\right)}}}=-{2}{x}-{4}\usepackage{cmbright}\Huge\$ would contain the points $\displaystyle{\left(-{1},-{2}\right)}\usepackage{cmbright}\Huge\$ and $\displaystyle{\left({1},-{6}\right)}\usepackage{cmbright}\Huge\$ , which are not on the graph. The correct answer is $\displaystyle{f{{\left({x}\right)}}}=-{2}{x}+{4}\usepackage{cmbright}\Huge\$ .