[tex]zad.a\\(2x+5y-3)-(x-6y+7)=2x+5y-3-x+6y-7=x+11y-10\\\\zad.b\\-(2a-4b+3c)-(-3a-4b+3)=-2a+4b-3c+3a++4b-3=a+8b-3c-3\\\\zad.c\\7+(3x-4y+2)=7+3x-4y+2=3x-4y+9\\\\zad.d\\5a-(2a-6b-1)=5a-2a+6b+1=3a+6b+1\\\\zad.e\\-(4x-5y-3)-(6x+3y+7)=-4x+5y+3-6x-3y-7=-10x-2y-4\\\\zad.f\\-(3ab+5bc)-(-2ab+4bc-2)=-3ab-5bc+2ab-4bc+2=-ab-9bc+2[/tex]
