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Source: IMO SL N5

July 17, 2019
number theoryIMO ShortlistdiophantineIMO shortlist 2018

Problem Statement

Four positive integers x,y,zx,y,z and tt satisfy the relations xyāˆ’zt=x+y=z+t. xy - zt = x + y = z + t. Is it possible that both xyxy and ztzt are perfect squares?