If you add a negative

Then you don't change the sign.

Two like signs become a positive sign.

Two unlike signs become a negative sign.

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!