Odpowiedź :
a) (3x + y) + (2x + 2y) =3x + y + 2x + 2y = 5x + 3y
b) (3x + y) – (2x + 2y) = 3x + y – 2x - 2y = x - y
c) (4x – 3y) + (x + 2y) – (2x - 3y) = 4x – 3y + x + 2y – 2x + 3y = 3x + 2y
d) - (x + 4) + (x – 5) = - x - 4 + x – 5 = - 9
e) (4x² - 3x) – (x + x²) – (x² - x) = 4x² - 3x – x - x² – x² + x = 2x² - 3x