The correct option is E x=y=z or none of the above relationship is established
I.
(x+y)3=1331⇒x+y=11⇒y=11−x
From equation III,
x (11−x)=28⇒11x−x2=28⇒x2−11x+28=0⇒x2−7x−4x+28=0⇒x(x−7)−4(x−7)=0⇒(x−7)(x−4)=0⇒x=7,4
From equation I
y=4,7
From equation II
7−4+z=0⇒z=−34−7+z=0⇒z=3