Triangles $JKL$ and $MNO$ are congruent, with $J$ corresponding to $M$, $K$ to $N$, and $L$ to $O$. If $m\angle J=(2x{)}^{\circ }$, $m\angle K=(3x{)}^{\circ }$, and $m\angle O=(4x{)}^{\circ }$, what is the value of $x$?