Question

How do you simplify `3.5x-7.5x`?

Answer 1

Probably I confused things a bit!

Explanation:

You could simply subtract the numbers because the two terms are similar (they contain the `x` both of them) so you can subtract them simply operating on the numbers maintaining the `x` as it is; but I thought of a more interesting approach.

Let us write your operation as:
`35/10x-75/10x=` (which is the same thing)
take the common denominator `10` and write:
`=(35x-75x)/10=`
now subtract the numerators:
`=(-40x)/10=`
divide by `10`:
`=-4x`