$\displaystyle{3}={\log}_{{{3}}}{x}\usepackage{cmbright}\Huge\$ means $\displaystyle{{3}}^{{3}}={x}\usepackage{cmbright}\Huge\$ .

So $\displaystyle{x}={3}\cdot{3}\cdot{3}={27}\usepackage{cmbright}\Huge\$ .