(Original post by lmartynofficial)
just expand 2^30 and divide it by 8^9 and you'll get 8. therefore x is 3
Actually .... whilst this is not an ideal description

You can do

2^{30} = 2^{3^{10}} = 8^{10}

10 - 9 = 1

giving an answer of 8^1 = 2^3