If 8^2 = x, And x^2 = y. What is y^2?
Since y = x^2
y^2 = x^4 x= 8^2 (or 64) then y^2 = (8^2)^4 = 8^8 or 16,777,216
Just substitute:
(8^2)^2=y
8^4=y
y=8^4
y^2=(8^4)^2=8^8=(2^3)^8=2^24
Y^2=2^24