Problem Solving (PS) | Re: xy and yx are reversed two digit positive integers. If the difference

There are no calculations needed to solve this question!

The difference of a 2 digit number and its reverse is\(10x+y - (10y+x) = 9(x-y)\)

From the answer options, only Option C(4) can be the difference of x and y,
as 9(x-y) is a perfect square only if x-y = 4.
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