help me work this out.

Answer:
1/216
Step-by-step explanation:
Notice that x and y are being multiplied by each other. Anytime a number is being raised to a negative exponent, it means the result is on the bottom of the fraction. Normally 2^3=8/1 but 2^-3=1/8. It reciprocates. Positive exponents is repeated multiplication but negative exponent is repeated division.
So [tex]2^{-3} *3^{-3}=\frac{1}{8} *\frac{1}{27} =1/216[/tex]