A farmer is using an entire field to plant corn and beets. The part of his field on which beets are grown has a length of $\displaystyle{5}{x}-{y}\usepackage{cmbright}\Huge\$ and a width of x. The part of the field on which corn is grown has a length of $\displaystyle{5}{x}-{y}\usepackage{cmbright}\Huge\$ and a width of $\displaystyle{8}{y}\usepackage{cmbright}\Huge\$ . What is the total area of the field?