I think its feeling complicated, as you are using a matrix, and I don't see why you need that here. The 'simple' solution would be just to do
redSomething.animate({ transform: 't100,0' }, 2000);
In the string 't' = translate, and 100,0 is move x 100 to the right.
Note, if you already have a transform applied, you could try adding the string on the end of the current one, but its a bit trickier if its rotated already or something and you want it to move right.