gracie wrote:

xy and yx are reversed two digit positive integers. If the difference between them is a perfect square>10, what is the difference between x and y?

A. 2

B. 3

C. 4

D. 5

E. 6

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.

_________________

You've got what it takes, but it will take everything you've got