number properties

[sud21]

x is a positive integer. If both the units' digit of (x+1)^2 and the units' digit of (x+3)^2 are 1, what is the units' digit of x-3?

[rijul007]

x is a positive integer. If both the units' digit of (x+1)^2 and the units' digit of (x+3)^2 are 1, what is the units' digit of x-3?

those numbers which when squared give 1 as units digit are 1,9

let us say x+1 = 9
x+3 = 11
x = 8

x-3 = 5

Units digit for x-3 would be 5