Incorrect. Substitute the values $\displaystyle{a}={1}\usepackage{cmbright}\Huge\$ , $\displaystyle{b}={6}\usepackage{cmbright}\Huge\$ , and $\displaystyle{c}={9}\usepackage{cmbright}\Huge\$ into the quadratic formula: $\displaystyle{x}=\frac{{-{b}\pm\sqrt{{{{b}}^{{2}}-{4}{a}{c}}}}}{{{2}{a}}}=\frac{{-{6}\pm\sqrt{{{{6}}^{{2}}-{4}{\left({1}\right)}{\left({9}\right)}}}}}{{{2}{\left({1}\right)}}}=\frac{{-{6}\pm\sqrt{{{36}-{36}}}}}{{{2}}}\usepackage{cmbright}\Huge\$ . If you simplify this expression, what value do you get for x?