Respuesta :

you combine like terms.
-2x+9x
whatever answer that is you then combine the like terms -9+-1 the you just make an expression out of them.
gmany

[tex]-9+(-2x)+9x-1\qquad\text{combine like terms}\\\\=(-2x+9x)+(-9-1)=\boxed{7x-10}[/tex]