Respuesta :

8x^2 + 2x - 9 - (3x^2 - 5x - 1) =
8x^2 + 2x - 9 - 3x^2 + 5x + 1 =
5x^2 + 7x - 8 <===
[tex](3x^2-5x-1)-(8x^2+2x-9) =3x^2-5x-1-8x^2-2x+9 =3x^2-8x^2-5x-2x-1+9 =-5x^2-7x+8 [/tex].