$ sudo apt-get remove dhcp-helper 

Uninstall dhcp-helper including dependent package

If you would like to remove dhcp-helper and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove dhcp-helper 

Use Purging dhcp-helper

If you use with purge options to dhcp-helper package all the configuration and dependent packages will be removed.

$ sudo apt-get purge dhcp-helper 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove dhcp-helper 

See Also,