Although this is a true equation, it is not the logarithmic form of the given equation. You have mixed up the b value and the y value. Remember that $\displaystyle{{b}}^{{y}}={x}\usepackage{cmbright}\Huge\$ is equivalent to $\displaystyle{\log}_{{{b}}}{x}={y}\usepackage{cmbright}\Huge\$ . Identify the values of the variables in the exponential equation and substitute them into the logarithmic equation.