SCalc$815\mathrm{.}3\mathrm{.}008.$

Evaluate the given integral by changing to polar coordinates.

$$

$$R

$(4$x $$ y$)$ dA$,$

where R is the region in the first quadrant enclosed by the circle

x$2+$ y$2=25$

and the lines

x $=0$

and

y $=$ x