Respuesta :

Original: (3x2 + 5x – 4) – (2x2 – 7x – 1)

3x^2 + 5x - 4 - 2x^2 - 7x - 1 < (Took parenthesis off)

First: Do 3x^2 - 2x^2 = x^2

x^2 + 5x - 4 - 7x - 1

Secondly: Do 5x - 7x = -2x

x^2 - 2x - 4 - 1

Third: Do -4 - - 1 = -4 +1 (Note: Subtracting 2 negatives will make it a positive) 

Answer: x^2 - 2x -3

HOPE THIS HELPS! ^_^