10a-3a+5a=?多少

问题描述:

10a-3a+5a=?多少

10a-3a+5a=12a8b-3b=?8b-3b=5ba+2a=10x-3x=5c-4c=y+9y= x+7x-4x=3a7xc10y4xc?对c?对是1c?对1习惯用法省略