Question

谁知道初一数学学探诊第二单元测试四的答案

Answer 1

-3p+3p-1=(3p-3p-1)=3p-(3p+1)；

（a-b+c-d)*(a+b-c+d)=[a-(b-c+d)]*[a-(c-d-b)]

3+(2x-y)-(y-x)=3+3x-2y; 2x-5a-(7x-2a)=-5x-3a