simplify
8^y+2 minus 34(2^3y) / (square root 8)^2y+1
why all the useless words? That's what math symbols are for!
(8^(y+2)-34(2^(3y)))/√8^(2y+1)
= (64*8^y - 34*8^y)/(√8 * 8^y)
= 30*8^y / (√8 * 8^y)
= 30/√8
= 15/√2
If I got the grouping wrong, fix it and redo the steps. But any other setup will provide a much less simple answer.