it is given that
the length of cords segments are
8 , 2x , 5x , 5
we know that when two chords intersect
the multiplication of the segments of the one chord will be equal the other chord
so,
[tex]8\times5=2x\times5x[/tex][tex]\begin{gathered} 40=10x^2 \\ x^2=4 \\ x=2 \end{gathered}[/tex]thus, the answer is x = 2