[tex]\frac{y}{n+4} = \frac{x+y}{n+2+n+4}[/tex]
[tex]\frac{y}{n+4} = \frac{x+y}{n^{2} +6}[/tex]
x+y= [tex]\frac{y(n^{2} +6)}{n+4}[/tex]
[tex]\frac{y}{n+4} =\frac{n+5}{n+3}[/tex]
y = [tex]\frac{(n+5)(n+4)}{n+3}[/tex] = [tex]\frac{n^{2} +9n+20}{n+3}[/tex]
x+y = [tex]\frac{n^{2} +9n+20}{n+3}[/tex] [tex]+ \frac{n^{2}+6 }{n+4}[/tex]
