3道N+1简单的题目,看看啊
问题描述：
3道N+1简单的题目,看看啊
判断这3道算式是否正确,错的订正（写出过程）
2(3x+5)-2(2x+3)
=6x+10-4x-3
=(6-4)x+(10-3)
=2x+7
4(5x+3)-3(2x-4)
=20x+12-6x-12
=(20-6)x+(12-12)
=14x
3ab-4a+2ab-5a-1
=(3+2)ab+(-4-5)a
=5ab-9a
答
2(3x+5)-2(2x+3)
=6x+10-4x-6
=(6-4)x+(10-6)
=2x+4
4(5x+3)-3(2x-4)
=20x+12-6x+12
=(20-6)x+(12+12)
=14x+24
3ab-4a+2ab-5a-1
=(3+2)ab+(-4-5)a -1
=5ab-9a-1