Odpowiedź:
a) 2x(x-4) - 5x = 2x * x - 2x *4 - 5x =
2x^2 - 8x - 5x = 2x^2 - 12x
b) 7x-3(x+8) = 7x - 3x - 24 = 4x - 24
c) 2x(a-3)+4(x-2) = 2x *a - 2x * 3 + 4*x - 4*2=
2ax - 6x + 4x - 8
d) - 4x(5+2x) + 2x(-2x - 5) =
- 4x *5 - 4x*2x - 2x *2x - 2x * 5 =
-20x - 8x^2 - 4x^2 - 10x = - 30x - 12x^2
