Answer: B) 16
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Step-by-step explanation:
Through trial and error, we can set up these equations
- 4^5 = 1024
- 2^10 = 1024
- 32^2 = 1024
This shows that choices A, C and D are eliminated. This is because 5, 10 and 32 all can work as either x or y in x^y = 1024, and that the other value is some other integer.
On the other hand, x = 16 doesn't work and neither does y = 16 if we wanted the other value to be an integer.
Solving x^16 = 1024 leads to approximately x = 1.5422 when we focus on the positive real number solution. This isn't an integer, so x^16 = 1024 doens't have any integer solutions.
Solving 16^y = 1024 leads to a similar situation as described in the previous paragraph. It doesn't have any integer solutions either (instead the value is y = 2.5)
So we have a few ways of arriving at why choice B is the final answer.