Exercitiul 4 va roggg multtt

x=9+√20
x=9+2√5
x+y/2=3√5-1
9+2√5+y/2=3√5-1
9+2√5+y=2(3√5-1)
9+2√5+y=6√5-2
y=6√5-2-(9+2√5)
y=6√5-2-9-2√5
y=4√5-11