Chapter 7 - Exponents and Exponential Functions - 7-2 Multiplying Powers With the Same Base - Practice and Problem-Solving Exercises - Page 429: 17

$x^{-1}y^{3}$=$y^3/x$

When we multiply two numbers with different exponents but the same base, we raise the base to the power of the two exponents added together. Thus, we know that x should be raised to the power of 5+(-6), which equals -1. We know that y should be raised to the power of 2+1, which equals 3. Our answer, $y^3x^{-1}$, can be rewritten as: $y^3/x$.