To check the current installed version of DirextX in your system, click on “start” menu and then select “Run”. You can also press “Windows Key”+”R” keyboard shortcut to open run dialog. In run dialog, type “dxdiag” without quote and then click ok. You will see the window of DirextX Diagnostic tool. In the system tab, see under System Information section. You will find the DirextX version number.
How to Install Latest version of Direct X
If you have enabled the automatic updates, Microsoft will update your software including DirectX automatically when the update is available for your system. But this is not the case if you have disabled the automatic updates. You will have to update software and drivers manually. If your system has older version of DirextX, you can update it by downloading platform updates for your operating systems.
You can find details here: Download Dirext X Update
You can also use this Link to search for directX and download the installer.