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