Question

Which expression is equivalent to -(5y)^-4 ?

A. 625/y^4
B. -625/y^4
C. 1/625y^4
D. -1/625y^4

Answer 1

The first step for solving this expression is to express it with a positive exponent using
`a^(-n) = (1)/( a^(n) )`.

`- (1)/((5y)^(4) )`
According to the exponent rules,, to raise a product to a power you must raise each factor to that power. This rule will change the expression to the following:

`-(1)/(625 y^(4) )`
This makes the correct answer to your question
`-(1)/(625 y^(4) )`,, or option D.
Let me know if you have any further questions.
:)