A window has the rectangle surmounted by a semi circle the t

A window has the rectangle surmounted by a semi circle the total perimeter of window is 14 and window has a maximum area
Find the ratio of the semicircle to the height of the rectangle
Show work

2*r+2*l+pi*r=14 l=(14-2*r-pi*r)/2 Area=l*2*r+1/2*pi*r^2 =(14-2*r-pi*r)/2*2*r+1/2*pi*r^2 derivative=14-4*r-2*pi+pi*r=0 r*(4+pi)=14 r=14/(4+pi)=1.96 l=1.96 ratio is 1