问题:
下列各式去括号正确的是
A.a2-(2a-b+c)=a2-2a-b+c
B.-(x-y)+(xy-1)=-x-y+xy-1
C.a-(3b-2c)=a-3b-2c
D.9y2-[x-(5z+4)]=9y2-x+5z+4
下列各式去括号正确的是
A.a2-(2a-b+c)=a2-2a-b+c
B.-(x-y)+(xy-1)=-x-y+xy-1
C.a-(3b-2c)=a-3b-2c
D.9y2-[x-(5z+4)]=9y2-x+5z+4
A.a2-(2a-b+c)=a2-2a-b+c
B.-(x-y)+(xy-1)=-x-y+xy-1
C.a-(3b-2c)=a-3b-2c
D.9y2-[x-(5z+4)]=9y2-x+5z+4
参考答案: