Answer :
[tex]2, 4, 5, 7, 9\ \ \ \Rightarrow\ \ \ median=5\\ \\ x, 2, 4, 5, 7, 9\ \ \ \Rightarrow\ \ \ median= \frac{4+5}{2} =4 \frac{1}{2}\\ \\ 2, 4, 5, 7, 9, x\ \ \ \Rightarrow\ \ \ median= \frac{5+7}{2} =6\\ \\ 2, 4, 5, x, 7, 9\ \ \ \Rightarrow\ \ \ median= \frac{5+x}{2}\\ \\.\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \frac{5+x}{2}=5\ \ /\cdot2\\ \\.\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 5+x=10\\ \\.\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x=5[/tex]