去括号：(1).-(x-1)=（2）.2(-a+1/2b)=(3).-1/2(y-2z)=(4)-0.2(5*5x+1)=
问题描述：
去括号：
(1).-(x-1)=
（2）.2(-a+1/2b)=
(3).-1/2(y-2z)=
(4)-0.2(5*5x+1)=
答
(1).-(x-1)=-X+1
（2）.2(-a+1/2b)=-2a+b
(3).-1/2(y-2z)=-1/2y+z
(4)-0.2(5*5x+1)= -5x-0.2