已知|2-x|与|x-y+4|互为相反数,求代数式
展开全部
绝对值都是大于等于零的,现在两个绝对值互为相反数,因为是绝对值,不可能是一正一负的情况,那么,只有两个绝对值都为零
所以有:
2-x==0,x-y+4==0
==>解出x=2,y=6
∴3(x-y)-5(x-y)*2-3(x-y)+(y-x)*2-4(x+y)+3(y-x)
==3(x-y)-5(x-y)*2-3(x-y)-(x-y)*2-4(x+y)-3(x-y)
==(x-y)(3-5-3-2-3)-4(x+y)
==-10(x-y)-4(x+y)
==-10(2-6)-4(2+6)
==-10×(-4)-4×8
==40-48
==-8
所以有:
2-x==0,x-y+4==0
==>解出x=2,y=6
∴3(x-y)-5(x-y)*2-3(x-y)+(y-x)*2-4(x+y)+3(y-x)
==3(x-y)-5(x-y)*2-3(x-y)-(x-y)*2-4(x+y)-3(x-y)
==(x-y)(3-5-3-2-3)-4(x+y)
==-10(x-y)-4(x+y)
==-10(2-6)-4(2+6)
==-10×(-4)-4×8
==40-48
==-8
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询