Odpowiedź:
1) -(2xy + x + 3) - ( 3xy - x + 3) = -2xy-x-3-3xy+x-3 = -5xy-6
2)2(3a + b) - 2(a - b) = 6a+2b-2a+2b = 4a+4b
3) (4a - 1)(2 - 3a) = 8a-12[tex]a^{2}[/tex]-2+3a = 11a-12
4) (x + y)(x - 2) + (x - y)(x + 1) = [tex]x^{2}[/tex]-2x+yx-2y+[tex]x^{2}[/tex]+x- xy -y = 2[tex]x^{2}[/tex]-x-3y
5)(3a - 2b + 1)(3a - 2) - 4a(2a - 3b + 1) = 9[tex]a^{2}[/tex]-6a-6ab+4b+3a-2-8[tex]a^{2}[/tex]+12ab-4a = [tex]a^{2}[/tex]-7a+6ab+4b-2
