according to PEMDAS you have to work inside each set of parenthesis first, then exponents, then multiply so
(12-9)^3 simplified is 3^3 which = 9
now onto
[8^2/(1+7)]
1+7=8
8^2=64
now you have left
9 x (64/8)
64 divided by 8 is 8 so now you just have
9 x 8
which is 72
soooo the answer is 72