Which expression eqivalent to 27x^-2y^6/3x^5y^2z^9?

Answer 1

Learn to add/subtract exponents:

27x^-2y^6/3x^5y^2z^9
= 27/3 * x^(-2-5) y^(6-2) z^(0-9)
= 9 x^-7 y^4 z^-9
= 9y^4/(x^7 z^9)