Question Number 145768 by mathdanisur last updated on 07/Jul/21
$${x};{y};{z};{t}\in\mathbb{Z}^{+} \\ $$$$\begin{cases}{{xy}\:+\:{zt}\:=\:\mathrm{38}}\\{{xz}\:+\:{yt}\:=\:\mathrm{34}}\\{{xt}\:+\:{yz}\:=\:\mathrm{43}}\end{cases}\:\:\Rightarrow\:{x}+{y}+{z}+{t}=? \\ $$