(root number x-2 root number Y) (root number x+ root number y)=0

Because the root number x+ root number y>0, we need to solve the above equation:

Root number x-2 root number y=0

Root x=2 root y

Square of both sides: x=4y

So:

(y+2 times the root sign, xy)(2 times the root sign, xy)

=[y+2 root sign (4y? )] [8y root symbol (4y? )]

=(y+4y) (8y-2y)

= 6 out of 5