Y by pavel kozlov, deplasmanyollari, lazizbek42, NO_SQUARES, Adventure10, Mango247, Tastymooncake2
Four positive integers
and
satisfy the relations
Is it possible that both
and
are perfect squares?


![\[ xy - zt = x + y = z + t. \]](http://latex.artofproblemsolving.com/c/1/2/c1270bde8804f79a317ab5f5ad6231b3fabcc4e4.png)


This post has been edited 1 time. Last edited by djmathman, May 8, 2020, 11:22 PM
Reason: added period
Reason: added period