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If 5^(-5y)=(1)/(3125) and 9^(x)=(1)/(81)...

If `5^(-5y)=(1)/(3125)` and `9^(x)=(1)/(81)` ,then `x-y=` ______

A

`-5`

B

`-2`

C

`-3`

D

2

Text Solution

Verified by Experts

The correct Answer is:
C
`5^(-5y)=(1)/(3125)`
`rArr 5^(-5y)=5^(-5)rArry=1`
`9^x=(1)/(81)`
`rArr 9^x=9^(-2)`
`rArr x=-2`
`therefore x-y=-2-1=-3`
Hence, the corret option is (c).
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