27 = x mod 5 9 = 1 mod y Find the min value of x^2 + y^2? Please explain on how to solve this question!

X = 2 (that is the remainder when 27 is divided by 5)
9 = y*k + 1 where k is a natural number.
The smallest absolute value of y which satisfies the above equation is 2 as 9 = 1 (mod 2)

So, the minimum value of x^2 + y^2 = 5.

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