11. If 8x=(4y)^2 and x=8, where y is an integer, which one can be the value of 4y?

A.-6
B.4
C.2
D.-4
E.-8

1 answer

if x=8, 8x = 64
so, now you have (4y)^2 = 64
Since 64=8^2, 4y can be 8 or -8