(1)错误2(3x+y)=6x+2y
(2)正确6(x-2)=6x-12
(3)错误-7(x+3)=-7x-21
(4)正确8(a+1)=8a+1
(5)错误-(a-10)=-a+10
(6)错误-a+b=-(b-a)
(7)正确2-3x=-(3x-2)
以上都是正确答案,希望能够帮到你
(1)错误2(3x+y)=6x+2y
(2)正确6(x-2)=6x-12
(3)错误-7(x+3)=-7x-21
(4)正确8(a+1)=8a+1
(5)错误-(a-10)=-a+10
(6)错误-a+b=-(b-a)
(7)正确2-3x=-(3x-2)
以上都是正确答案,希望能够帮到你