合并下列各式的同类项 1.-(5x-y-2z)-3[4x-(x-y-z)+2y]
问题描述：
合并下列各式的同类项
1.-(5x-y-2z)-3[4x-(x-y-z)+2y]
答
原式=-5x+y+2z-3[4x-x+y+z+2y]
=-5x+y+2z-12x+3x-3y-3z-6y
=(-5-12+3)x+(1-3-6)y+(2-3)z
=-14x-8y-z
答
原式=-5x+y+2z-3[3x+3y+z]
=-5x+y+2z-9x-9y-3z
=-14x-8y-z
答
.-(5x-y-2z)-3[4x-(x-y-z)+2y]
=-5x+y+2z-12x+3(x-y-z)-6y
=-5x+y+2z-12x+3x-3y-3z-6y
=-14x-8y-z