(1)-( )=2a-b (2)a-b+c=a-( ) (3)2( )-x的平方+3=3x的平方-5 (4)(3m-1)+( )=5m+2

问题描述:

(1)-( )=2a-b (2)a-b+c=a-( ) (3)2( )-x的平方+3=3x的平方-5 (4)(3m-1)+( )=5m+2

(1)-(b-2a)=2a-b
(2)a-b+c=a-( b-c)
(3)2(2x^2-4)-x^2+3=3x^2-5
(4)(3m-1)+(2m+3 )=5m+2