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a) 25^{3x}= 1/5^{2-x}

This is what i've done but i don't know if it's right so i need someone to check it for me please.

(5^{2})^{3x}= (5^{-1})^{2-x}

6x = -2+x (x powers)

5x=-2

x= -2/5

b)3x^{-1/2}- 4 = 0

errm....i'm kinda stuck on this one, could someone start me off please?

3x^{-1/2}= 4

c) find the value of y

4^{y+1}=8^{2y-1}

here's what i did:

(2^{2})^{y+1}= (2^{3})^{2y-1}

2y+2=6y-3 (powers)

4y-5=0

y=5/4

Is that right?

Thanks in advance!

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# Equations -check pls!

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