The hose will add 8 gallons after one minute, $\displaystyle{8}\cdot{2}={16}\usepackage{cmbright}\Huge\$ gallons after two minutes, $\displaystyle{8}\cdot{3}={24}\usepackage{cmbright}\Huge\$ gallons after three minutes, or $\displaystyle{8}{x}\usepackage{cmbright}\Huge\$ gallons after x minutes. Since the pond already has 10 gallons in it, the total amount of water in the pond will be $\displaystyle{y}={8}{x}+{10}\usepackage{cmbright}\Huge\$ after x minutes.