You may only have found the constant of variation for the first direct variation equation. Once you have found the constant $\displaystyle{k}={5.50}\usepackage{cmbright}\Huge\$ , substitute this number, along with $\displaystyle{y}={154}\usepackage{cmbright}\Huge\$ , into $\displaystyle{y}={k}{x}\usepackage{cmbright}\Huge\$ and solve for x.