exponential problem: if 5^x=128 125^y=32 then (2x+y)/(4y-x) = ?

ketanco

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5^x=128
125^y=32

then

(2x+y)/(4y-x) = ?

i tried writing in terms of each other but could not solve

the answer is -47 , but dont know how to obtain it
 
5^x=128
125^y=32

then

(2x+y)/(4y-x) = ?

i tried writing in terms of each other but could not solve

the answer is -47 , but dont know how to obtain it
x = log(128)/log(5)
y = log(32)/log(125)

Are you allowed to use logs?
If so, above will give -47
 
5^x=128
125^y=32

then

(2x+y)/(4y-x) = ?

i tried writing in terms of each other but could not solve

the answer is -47 , but dont know how to obtain it

If you don't choose to use logarithms, you can rewrite the equations as

5^x = 2^7
5^(3y) = 2^5.

Then raise the first equation to the 5th power, and the second to the 7th power, and you can find the ratio y/x. Use that in the requested expression.
 
If you don't choose to use logarithms, you can rewrite the equations as

5^x = 2^7
5^(3y) = 2^5.

Then raise the first equation to the 5th power, and the second to the 7th power, and you can find the ratio y/x. Use that in the requested expression.

yes i was able to solve it like this. thanks !
 
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