去括号并化简:2(a+b)+3(a-b)=() ,2x²-3y-2(x²-2y)

问题描述:

去括号并化简:2(a+b)+3(a-b)=() ,2x²-3y-2(x²-2y)

2(a+b)+3(a-b)=2a+2b+3a-3b=5a-b
2x²-3y-2(x²-2y)=2x²-3y-2x²+4y=y