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Bunuel
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Bunuel
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abhilash53
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Hello,

How does the left hand side of this equation factor? ie the 28^18y

Sorry, a bit rusty on the the exponent rules. Thanks in advance.
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Hi Bunuel, if x & y are not integers, does it give infinitely many solutions of x & y, or does it still give finite (but different) solutions? Thanks!
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Bunuel
Hi Bunuel, if x & y are not integers, does it give infinitely many solutions of x & y, or does it still give finite (but different) solutions? Thanks!

It will have infinite number of solutions. For every x, there will be some y to satisfy the equation and vise-versa.
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Please let me know where I am going wrong?
8^-12= 4^-18y

4^-24 = 4^-18y
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Please let me know where I am going wrong?
8^-12= 4^-18y

4^-24 = 4^-18y

8^(-12) does not equal to 4^(-24).


8^(-12) = (2^3)^(-12) = 2^(-36), while 4^(-24) = (2^2)^(-24) = 2^(-48).
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I have edited the question and the solution by adding more details to enhance its clarity. I hope it is now easier to understand.
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I think this is a high-quality question and I agree with explanation.
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I like the solution - it’s helpful.
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We can rewrite as

(1/7)^x * (1/2)^36 = (1/7)^18y * (1/2)^36y

We can quickly see that y must be 1, because (1/2)^36 must be equal to (1/2)^36y.

So (1/7)^x = (1/7)^18y;

Which means that x = 18y,

So x = 18 * 1 = 18.

y - x = 1 - 18 = -17.

Answer B.
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