I read this as (18(x2y)3)/(9x6).
Let's deal with the numerical constants first:
(2(x2y)3)/(x6).
Let's expand (x2y)3. All the exponents inside parentheses are to be multiplied by 3:
x6y3. But we also have x6 in the denominator so it cancels x6 in the numerator leaving us with the solution:
2y3.