The decline of salmon fisheries along the Columbia River in Oregon has caused great concern among commercial and recreational fishermen. The paper 'Feeding of Predaceous Fishes on Out$-$Migrating Juvenile Salmonids in John Day Reservoir, Columbia River' $($Trans$.$ Amer. Fisheries Soc. $(1991$: $405-420))$ gave the accompanying data on y $=$ maximum size of salmonids consumed by a northern squaw fish $($the most abundant salmonid predator$)$ and x $=$ squawfish length, both in mm$.$ Use the following statistics to give the equation of the least squares regression line.

x $=524\mathrm{.}970,$ y $=319\mathrm{.}417,$ sx $=19\mathrm{.}943,$ sy $=16\mathrm{.}100,$ r $=0\mathrm{.}9662$