(1)3a-7a (2)-3xy+5xy (3)-x+2x-x (4)-4a²b+3ba² (5)3分之2x³-3x³3(x-y)-7(x-y)

问题描述:

(1)3a-7a (2)-3xy+5xy (3)-x+2x-x (4)-4a²b+3ba² (5)3分之2x³-3x³
3(x-y)-7(x-y)