error i recieved trying to install gnome tweak tool

[StephanB9]

hey everyone im super new at using linux as in today lol anyways ive been trying to set up gnome tweak tool by using the command apt-get install gnome-tweak-tool however it did not work after trying many random things i found online every time i try to use the command apt-get update i get this error message. can some one please help to fix this or do i need to do a fresh install the error is as follows E: Type 'x' is not known on line 1 in source list /etc/apt/sources.list
E: The list of sources could not be read.

[g0tmi1k]

Either you (or something you ran), has altered your source file: /etc/apt/sources.list
This isn't recommended at all - which is why your kali install is now broken.
For more information (including what it should be): http://docs.kali.org/general-use/kal...t-repositories