Help me pls and pls explain

Step-by-step explanation:

I am not clear your question.

5^(-2) / ( 5^(-3) * 5^(4))

When base is equal at multifaction index should be add.

ie. (-3)  + 4 =1

5^(-2) / ( 5^((-3) +4))

5^(-2) / ( 5^(1))

When base is equal at division index should be substract.

5^(-2) / ( 5^(1))

5^((-2 )+ (-1) )

5^(-3)

We know a^(-2)= 1/ a^2

1/ 5^(3)

the answer is y < -3 or   y > 3

-3y > 7 + 2

-3 y > 9

y < -3