Brother MFC-7420 Scanning & Faxing Quick Start for Ubuntu 15.10 Wily
You are Welcome! The Tutorial shows you Step-by-Step How to Install and Getting-Started with Brother MFC-7420 Laser Printer Scanner on Ubuntu 15.10 Wily Werewolf i386/amd64 GNU+Linux Desktop.
Included inside the Article a Link to Guide about Getting-Started with Brother MFC-7420 Fax on Ubuntu 15.10 Wily Linux.

-
Open a Terminal Shell emulator Window
Ctrl+Alt+t on desktop
(Press “Enter” to Execute Commands) -
Download Brother MFC-7420 Printer Scanner Linux Drivers
Select the Brother MFC-7420 Scanner Drivers for Ubuntu.
-
Checking/Installing GDebi Package Installer.
which gdebi
If Not there then:
sudo apt-get install gdebi gdebi-core
If Got “User is Not in Sudoers file” then see: How to Enable sudo
-
Installing Brother Scanner Driver
cd ~/Downloads
sudo gdebi brscan*.deb
-
How to Quick Start Faxing with Brother MFC-7420 Printer on Ubuntu