How do i factor the coefficent out of a variable, such as 2.4n+9.6 and - 6z+12

You are factoring one or more linear expressions (but are not factoring variables).

2.4n+9.6 can be divided by 2.4 and then the result mult. by 2.4:

2.4n+9.6 = 2.4 [ n + 4 ]

Also: - 6z+12 = 6 [ - z + 2 ] Here I have simplified linear functions but factoring out common constant coefficients (not variables).