The value of $\Delta H$ for the reaction $X_2\left(g\right)+4Y_{2}9g)\iff 2X{Y}_4\left(g\right)$ is less than zero. Formation of $X{Y}_4\left(g\right)$ will be favoured at $:$

$X_2\left(g\right)+4Y_2\iff 2X{Y}_4\left(g\right)$, where $\Delta H<0$ and $\Delta n<0\left[\Delta n=n_p-n_R\right]$
$\therefore$ The forward reaction is favoured at high pressure and low temperature.(According to Le -chatelier's principle).