Replace x = 5 and y = 4 into the given equations,we have :

{5k−4m=75m+4k=22⇒{20k−16m=2820k+25m=110

⇒⎧⎨⎩41m=82k=4m+75⇒{m=2k=3

Replace x = 5 and y = 4 into the given equations,we have :

\(\left\{{}\begin{matrix}5k-4m=7\\5m+4k=22\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}20k-16m=28\\20k+25m=110\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}41m=82\\k=\dfrac{4m+7}{5}\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}m=2\\k=3\end{matrix}\right.\)