This is a domain that x10hosting owns and it's an option for you if you choose. It can't be changed that way. Please choose a different domain extension if you must. There are others available to choose from such as: .x10.bz, .pcriot.com, elementfx.com, .exofire.net, and even .co.cc (you must register at co.cc yourself and set the nameservers there because this domain is not owned by x10hosting). You can change your domain in your account panel
https://x10hosting.com/control/login.php, click on hosting details, click to modify hosting details, and then change the domain there by choosing from the droplist.