What is the value of X?What is the length of JK?

The figure above is a kite . The 2 pairs of adjacent sides are equal. Therefore,
[tex]\begin{gathered} x+5=2x-7 \\ x-2x=-7-5 \\ -x=-12 \\ x=12 \end{gathered}[/tex][tex]\begin{gathered} JK=x+5 \\ JK=12+5=17 \end{gathered}[/tex]