Odpowiedź:
a)
2x(x - 4) - 5x =
= 2x * x - 2x * 4 - 5x
= 2x² - 8x - 5x =
= 2x² - 13x
b)
7x - 3(x + 8) =
= 7x - 3 * x - 3 * 8 =
= 7x - 3x - 24 =
= 4x - 24
c)
2x(a - 3) + 4(x - 2) =
= 2x * a - 2x * 3 + 4 * x - 4 * 2 =
= 2xa - 6x + 4x - 8 =
= 2xa - 2x - 8
d)
- 4x(5 + 2x) + 2x(- 2x - 5) =
= - 4x * 5 - 4x * 2x - 2x * 2x - 2x * 5 =
= - 20x - 8x² - 4x - 10x =
= - 24x - 8x²
