去括号:(1).-(x-1)=(2).2(-a+1/2b)=(3).-1/2(y-2z)=(4)-0.2(5*5x+1)
去括号 (1)-(x-y-z)=______ (2)-[-(a+b)]=_____ (3)2(3x-2y)-3(2x-3
2(-a+二分之一b)-二分之一(y-2z) -0.2(5x的二次方+1) 去括号
解二元一次方程(1)a-b+c=4 a+b+c=3 2a+b+c=3(2)x-y-z=5 y-z-x=1 z-x-y=1
(-2a-b)②-(-2a+b)(-b-2a) (x-y+z)(-x+y+z)+(x-y)②其中z=-1
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
解方程组2x/a+3y/b-4z/c=1,4x/a+2y/b-3z/c=3,3x/a+4y/b-2z/c=5
x-4(y-x).3x-2(5x+y)=.去括号 化简 .化简 12-3[4a-3(a-2)].1分钟
{5x-3y+z=2{5x+2y-4z=3{-5x+y-z=2 {x-y-z=-1{3x+5y+7z{4x-y+2x=-
已知x/3=y/4=z/5≠0,3x+2y-5z/x+y+z的值;已知a/b=1/3,求a-b/b
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
(1)3x+4z=7;2x+3y+z=9;5x-9y+7z=8 (2)3x+4y+z=14;x+5y+2z=17;2x+
(1){x-y=2 z-x=3 y+z=-1 (2){x-y-z=2 3x+5y+7z=24 4x-y+2z=26